Pesticides Handling, Risk Management and Estimation of Exposure Levels in Potato Farming Under Small Scale Production

doi:10.21203/rs.3.rs-2889820/v1

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Pesticides Handling, Risk Management and Estimation of Exposure Levels in Potato Farming Under Small Scale Production

https://doi.org/10.21203/rs.3.rs-2889820/v1

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Management of biotic stresses in agriculture solely depends on the use of pesticides globally. Little is currently known on the health risks attributed to pesticides in potato farming in Kenya. The level of exposure and safety precautions adopted by operators to avoid hazards attributed to handling of chemicals and develop an easy to use model of exposure in potato farming was investigated. A total of 197 potato farmers from Nyandarua County in Kenya were interviewed using a structured questionnaire. Data on pesticides handling parameters were collected. Results revealed that, most hazardous chemical (WHO class III) were highly (75%) used, whilst biologicals were unfamiliar to farmers. Majority of farmers were in agreement that, pesticides posed health risks (85%) and (90%) environmental impairment. Only 46% of the farmers were aware of pesticides safety, while 36% used personal protective equipments (PPEs) when handling pesticides. In addition, the percentage of farmers who could read and understand chemical label was 30%. Trained and educated farmers were more likely to follow pesticides safety precautions (88%). Poor disposal of chemical leftovers and empty containers was evident whereas most farmers (86%) had no standard storage facility for pesticides. Lack of training (70%) was pointed out as the major constrain. Merely, 10% experienced self-reported symptoms of acute poisoning. Estimation of exposure elucidated that, potato growers are at high risk to metalaxyl and mancozeb exposure. Therefore multi-institutional interventions would be crucial in providing sustainable solutions.

Pesticides

Health risks

Pesticides handling

Disposal

environmental hazard

In recent years, pesticides have become an integral part of modern farming practices to manage biotic and abiotic stresses to improve on crop production by 70% in response to increase in food demand following the growing world population. Worldwide, about 26% (1.8 billion people) of the population are engaged in farming whom embrace pesticides to guarantee healthy crop and food security (Grube et al., 2011) with possibility of undermining the natural ecosystem. Sustainable solutions to the global challenge of feeding the global population with negligible risks to biodiversity include, use of biological compounds. A number of biopesticides and non-synthetic chemicals have been developed over the last decade in managing insects, weeds, diseases and other pests (Khan et al., 2010). It is estimated that, the amount pesticides traded in 2020 increased by 13.8% corresponding to about 40.8 from 35.8 billion US dollars, globally. About two thirds of the pesticides traded annually worldwide is attributed to Europe while Africa account to about 4% (FAO, 2021).

Indiscriminate and extensive usage of pesticides on potato globally has been reported to be unscientific and unregulated (Aktar et al., 2009). Owing to the nature of pesticides, their usage has raised a number of key issues concerning risks associated with the chemicals worldwide (Bonner and Alavanja., 2017; Machado and Martins, 2018) including devastating risks to human health (Ejaz et al., 2004; Jensen et al., 2011) and ecosystem (Sharma et al., 2019) depending intrinsic properties of the pesticide, bioavailability and duration of exposure, with trade-off between the increase in food production and human health remains unclear. Inhalation and dermal are the major routes of exposure following loading, mixing, spraying, repairing and cleaning of applicators (Camilo, 2014). A number of chronic toxicities and fatalities have been reported among farm families due to occupational, accidental and intentional poisoning (Sabarwal et al., 2018). For instance, exposure to pesticides is linked with health ailments including Parkinson disease (Brouwer et al., 2017) Hodgkins disease (Luo et al., 2016) endocrine disruption (Mazur et al., 2015). Besides, the improper use of chemicals is associated with pest resurgence, pathogens mutations, destruction of non-target pest (Atreya et al., 2011) and ultimate accumulation of residue in primary and derived agricultural products (Kilonzi et al., 2021). Despite this strides, policies, regulations and training materials for enhancing pesticides use is still in their infancy in most developing countries.

Interests on growing potato have increased tremendously in the last few years in Kenya. However, prevalence of pathologies including late blight and insect pest has occasioned extensive utilization of pesticides owing to favourable conditions in the potato production regions. Weekly sprays have been reported in a number studies in highland production regions (Kilonzi et al., 2020; Nyankanga et al., 2007). Consequently, multiple application is often associated with prolonged exposure to pesticides prejudicing farm workers to health risks as result of toxicities through contact with residue in crop products, unsafe handling during application and cleaning of chemical applicators, storage and disposal of chemical leftovers and empty containers (Kim et al., 2017). A number of insecticides and merely few nematicides have been adopted by farmers (Macharia, 2015). A study conducted by Kachaiyaphum et al. (2010) revealed that common signs of exposure include; headaches, nausea, respiratory depression and deaths. Limited knowledge on contaminated potato tubers and potato products, access and use of protective gears, lack of institutional support to capacity build chemical applicants and farmers and ignorance and perceptions of pesticides could be the exacerbating exposure level. Much trainings have been geared towards production with less attention on sustainable management approaches. Damalas and Eleftherohorinos (2011) reported that, less educated farmers experience difficulties in understanding chemical labels and risks associated with the pesticide. Inadequacy implementation of safety measures has been a perennial challenge in Kenya. Consequently, farmers face risks of acute and chronic toxicities, pesticides residue, contamination of environment and ultimately deaths

Correspondingly, a number of interventions have been proposed including implementation of Integrated Pest Management (IPM) strategies to formulate sound policies (Lamichhane, 2017). For instance, the European Union (EU) established a series of legislative intervention frameworks among others, Directive 89/391/EEC, Directive 2009/128/EC, Regulation (EC) No. 1272/2008, related acts, to enhance sustainable use of pesticides (Skevas et al., 2013). The regulations provided guidelines on safety of pesticides applying machinery and equipments, placing plant products in the market, classification, labelling, registration and restriction of chemicals (Dugger-Webster and LePrevost, 2018) to influence behaviour change of the agricultural operating companies and farmers. Preventive chemical management is currently embraced by a number of countries to embrace obligations concerning the whole cycle of pesticides use; from purchase to disposal of residues and empty packaging materials. In this perspective, a low pesticides input in farming corresponds to good agronomic practices and compliance to occupation health and safety measures, besides environmental conservation (Lechenet et al., 2016). Previous studies (Macfarlane et al., 2013); Macharia et al., 2013; Khan et al., 2015) addressing assessment of associated risks have focused on embracing education as a key pillar in the safety of agricultural chemicals following chemical utilization surveys to embrace sustainable pesticides welfare. Even with focused training and safety pictograms, attitude, knowledge and practices remains inadequate. However, the hypothesized trainings lacks quantitative data on exposure levels to foster guaranteed adoption of safety measures to mitigate harmful effects of the pesticides. Besides, there are many different chemicals been produced and released into the market following evolution of previous molecules

To reduce the mentioned gen gap, a farmer based simpler approach in substantiating the perils associated with pesticides through modelling of occupational health safety could abate this challenge. A number of prediction models have been previously proposed to estimate the level of exposure (Fargnoli et al., 2019). The tool focuses on accounting all risks attributed to pesticides encompassing all the phases involving pesticides handling. Considering the scale of production in Kenya, most farmers are medium to small scale producers of potatoes and therefore the easy to use prediction systems remain eminent. This models estimate the probability of occurrence and scale of risks attributed to pesticides. This is based on chemical toxicity level in reference to acceptable operator exposure level, exposure duration and body mass exposed. Nevertheless, estimating pesticides exposure in agricultural operations involving work environments and operators remains complex (Colosio et al., 2012). In developed countries, a number of studies have assessed farmers’ level of knowledge on pesticides use on various crops, but less research has been conducted on potato farming in Kenya. Therefore, in this study, we aimed at analysing awareness on pesticides, handling, perceptions on human health and environmental impacts as well as document pesticides commonly used in potato farming. Additionally, the level of exposure was estimated using existing models amended to match potato production practices and harmonization prediction systems globally. Understanding farmers’ knowledge on pesticides safe use is imperative not only in identifying knowledge gap and exposure levels, but also provide a valuable information for developing focused training need as well as policy instruments.

2.1 Questionnaire development

A formal face to face interview using structured questionnaire (supplementary material) loaded in Kobotool box collect software version 2022.1.2 was used to collect data on pesticides use, handling, risk awareness and safety practices from Nyandarua County. The survey was conducted in August to September, 2022. The County is one of the highest potato producing region. Description of the study area has been defined in County Goverment of Nyandarua (2017) report where Kipipiri, north Kinagop and south Kinagop sub counties were the focal areas of study. The sub counties account to about 90% of the total production in the county. Demographic information collected included; family size, highest education level and land acreage. Respondents were also shown chemical’s pictograms, colour codes and warning statements on the pesticide label to monitor their understanding. Using minimum sample size with respect to resources available, the number of respondents was calculated according to published tables (Singh and Masaku., 2011) and formula proposed by Krejcie and Morgan below, 197 representatives were purposively selected using cluster sampling from 48,000 families involved in potato production as well as chemical applicants.

$$n=\frac{{{\chi }}^{2}\text{N}\text{P}(1-\text{P})}{{d}^{2}\left(\text{N}-1\right)+ {{\chi }}^{2}\text{P}(1-\text{P}) }$$

Where: n = sample size, N = total number of potato growing farmers, ${{\chi }}^{2}$ = chi-square for specified confidence level at 1 degree of freedom or desired confidence level 0.05 = 3-841, P = percentage of farmers using pesticides (assumed to be 0.8), d = denoted margin error, degree of accuracy expressed as a proportion of 0.05 at 95% confidence level.

Questionnaire was designed in closed (with multiple responses that described their opinion) and open-ended questions. Pretesting was conducted in Limuru sub County of Kiambu County where 21 respondents participated to minimize reporting biaseness. Reliability and internal consistency conducted using Cronbach’s alpha formula where a value of 0.71 was obtained. The questionnaire consisted of two sections, firstly, basic information section that included information on age, education, land size, costs of pesticides application and chemicals used, and secondly on pesticides handling, that focused chemicals use (Respondents were first asked to list pathologies they encounter in potato farming before listing the pesticides), on use of PPEs, disposal of chemical leftovers and empty containers, storage of chemicals, risks awareness, reading and following of label instructions and self-reported symptoms attributed to pesticides toxicities. To reduce recall biasness due to under-reporting, only potato farmers who planted potato in the last two previous years were targeted.

2.2 Data analysis

Data was exported from kobotool box collect software to Microsoft excel (Microsoft Corporation, Redmond, WA, USA) file before analysis using Statistical Social Sciences Version 21 (IBM Corporation, Armonk, NY, USA). Descriptive statistics was also used to assess demographic information, access use of PPEs and exposure on the variance of dependent variables.

3.1 Demographic and profile characteristics of the potato farmers

From the survey results, a total of 99 (50.3%) were female, while male were 98 (49.7%) respondents. While during the short rain, 95.6% of farmers planted potato, 92.4% grew the tuber crop in long rain season. Majority of the farmers (53.3%) owned 0.5 to 1.0 acre parcel of land, below 0.5 acre (29.9%), followed by those whose land acreage under potato was between 1 and 2 acres (17%), while above 2 acres were the minority (7%). Whereas farming was done equally by both gender, pesticide application was majorly done by men, the latter had a higher level of education than the women. Majority of the respondents had attained secondary school education followed by high school drop outs, primary education, tertiary education and those did not complete primary education, in that order. Notably, education level implicated on the safety precautions employed while utilizing pesticides. On the other hand, farmers who received training (19%) on pesticides safe use by institutions presented in Figure 1 mainly had secondary school education while those with the highest (Tertiary education) and the lowest (those who did not complete primary education) education level were the least in number to participate or attend to safe use of pesticides (Table 1). Similarly, training on safe use of pesticides also implicated on pesticides hazards deterrents (Table 2).

Table 1: Percentage of respondents in the precautionary measures employed based on their education level

Education Level	Frequency (n)	Reading label (%)	Use of PPEs (%)	Checking expiry (%)	Confirming registration by PCPB (%)	Knowledge on health hazards (%)	Knowledge on environmental hazards (%)	Received training (%)
Tertiary education	18	94	61	100	72	100	100	5
Secondary school	83	83	63	86	70	66	65	85
Incomplete secondary school	49	61	47	78	43	61	57	60
Primary school	34	74	41	44	29	35	41	80
Incomplete primary school	13	25	33	58	17	50	50	20

Table 2: Relationship between reading label and checking expiry and PCBP Expiry and training

If the farmer was trained on pesticides use

Frequency

(n)

Reading label

(%)

Use of PPEs (%)

Checking expiry (%)

Confirming registration by PCPB (%)

Knowledge on health hazards (%)

Knowledge on environmental hazards (%)

Trained

Untrained

160

3.2 Knowledge and understanding of pesticides handling among farmers

From the chemical applicants’ and farmers’ perspective, 93.4% of the respondents suggested that chemical pesticides provides solutions to biotic stresses and whom expressed their reasoning (Table 3). However, farmers conveyed a number of constrains while purchasing pesticides (Table 4). Genderwise, males were the most reported (62.9%) as chemical applicants aged between 36 and 45 years (42.1%). Notably, the aged (above 60 years) were least (3%) involved in pesticides application. The highest education level of the chemical applicants was secondary school (42.1%) followed by those who attended secondary school but never completed (24.9%). Results reveal that those untrained or who do not read the label, depended on agrodealer’s (72%), fellow farmers (15%) and relatives (13%) on pesticides use guidance.

Merely, 42.1% of the respondents purchased personal protective equipments (PPEs) for pesticides application during the survey period Table 4. Despite the fact that the number of respondents who had received training on pesticides safe use were 18.8% and reported a number of constrains (Table 4) in accessing the service, only 88.3% and 75.6 % of the chemical applicants were cognisant on the human health and environmental concerns respectively posed by pesticides respectively (Table 5). However, 86.3% of the respondents were able to ascertain whether the pesticides were banned or expired. On the contrary, only 22.8% of the farmers were able to check whether the pesticide was registered by Pests Products and Produce Board (PCPB). Unexpectedly, 3.6% of the respondents purchased expired chemicals whom either returned to the agro-dealer, buried them or dumped in the environment. Only one chemical applicant went ahead and applied the chemical.

Pertaining application efficiency, only 38% of the chemical applicants/farmers calibrated their knapsack in which it was done two months prior to planting season.

Table 3: Respondents feedbacks on whether chemical pesticides are a solution to food production

Reasons why farmers thought chemical pesticides are a solution to food production	Percentage (n=184)	Reasons why farmers thought chemical pesticides are not a solution to food production	Percentage (n=13)
Boost production in terms of quality	7.3	Because long ago chemicals were not used	15.4
Promote plant growth and good crop stand	3.3	Pose human health risks due to residues in crop products	7.7
Assist in controlling pests	52.3	Some chemicals are fake	7.7
Minimize labour cost	3.8	Good produce than when one has not used pesticides	15.4
Are a solution to food security when high yields are achieved	19.0	If you plant with manure no need of chemicals	15.4
Because crops stand a chance against cold weather	3.3	Some do not work effectively on potatoes	15.4
Because potatoes are stronger and recover from stress after spraying	2.3	Sometimes they cause damage to crops	7.7
Save on time for other activities	5.4	There is need for sustainable solutions like biologicals	15.4
No other effective method of controlling Late Blight	3.3

Table 4: Constrains that farmers face when accessing training opportunities and purchasing pesticides, and PPEs

Constrains faced by farmers when purchasing pesticides	Percentage (%) (n=169)	Constrains faced by farmers when purchasing PPEs	Percentage (%) (n=114)	Constrains faced by farmers when accessing training	Percentage (%) (n=160)
Affordability	49.3	Affordability	48.6	Distance to the institution is far	47.2
Availability at the agrostockist	13.1	Availability at the agrostockist	27.5	I don’t have time to read the materials	20.8
Distance to agrostockist	14.2	Distance to agrostockist	9.1	I don’t know which institute to approach	32.0
Knowledge on which chemicals to buy	23.4	Ignorance	14.8

Table 5: List of hazards paused by pesticides

Human health related hazards	Percentage of respondents (%)	Environmental related hazards	Percentage of respondents (%)
Headaches,	11.6	Bad smell	2.5
Respiratory diseases	16.2	Affects animals when they eat grass where chemicals are dumped	10.2
Cancer	11.7	Land pollution	21.8
Skin irritation	16.2	Water pollution	19.3
Allergies	12.2	Air pollution	16.2
Blood pressure changes	5.1	soil degradation	7.6
Skin problems	6.6	Can pollute soil	3.6
Chest problem	4.1	Climates change	1.0
Damage to body organs	3.6	Kill microorganisms	8.6
Dizziness	3.6	Damage of ecosystem	4.1
Irritation	6.1	Kill useful insects	5.1
Death	3.0

3.3 Farmers Knowledge on Pesticide Risk Awareness and Management

Survey results suggested that, only 7% of the chemical applicants had received training on safe use of pesticides and a vast number of the applicants had more 9 years (36%) experience in applying pesticides which did not reflect the safety in the use pesticides (Table 6). None of the chemical applicant was a service provider. Pertaining understanding of chemical label information, 49.7% and 56.9% of the farmers could translate the information on colour codes and warning statements respectively. About 54.3% of the farmers purchased chemicals in bulk, in which majority (49%) kept the chemicals in their house while unexpectedly those who had store were 24% (Figure 2). To observe precautions, about 64.8% of the chemical applicants read and followed instruction on the chemical label (Figure 3), and apparently 72.6% used PPEs when handling chemicals. However, the PPEs were either in bad condition (70%); torn and not covering target part of the body or were not full kit (90%). Proportion of chemical applicants using PPEs to repair knapsack, mix and apply pesticides were 47.2%, 65% and 64% respectively. The habitual use of PPEs is as presented in Table 7 and Table 8. About 86% of the farmers observed re-entry period, while 7% were not aware of the re-entry guidelines. In the field, majority of farmers considered wind (80.2%), time of the day (83.1%), soggy field (21.3%) and rainy period (93.4%) before applying pesticides.

Methods of unblocking nozzles was done by use of wire and water (58.1%), blowing with mouth (36.7%) and replacement of faulty nozzle (0.5%), but only 2.5% did nothing to correct the defect (Figure 4). About 30% of the chemical applicants applied chemical pesticide following the recommendations of the manufacturer (Figure 5). From the survey, results revealed that most chemical applicants did not take food while spraying (98%) or mixing (96%) the pesticides. After chemical applications, the applicants took bath immediately (85%) and only 19% washed their hands after spraying, while merely 6% never cleaned their body and took fluids as proportionately presented in Figure 6.

Table 6: Knowledge index (KI) on safety precautions in relation to years of experience

Years in experience	Frequency (n)	Reading label (KI)	Use of PPEs (KI)	Checking expiry (KI)	Re-entry period (KI)
Less than 1	4	0.50	0.25	0.75	0
Between 1 and 2	15	0.84	0.33	0.94	0
Between 2 and 4	61	0.98	0.52	0.98	0.33
Between 4 and 9	47	0.78	0.60	1.00	0.43
More than 9	70	0.99	0.67	0.99	0.71

KI based on scale of 0 (unware) to 1(fully aware) out of total number of respondents

Table 7: Use of PPEs while applying pesticides

Personal protective equipment	Percentage (n=128)	Variable
Personal protective equipment	Percentage (n=128)	Good	Fair	Bad
Full kit	24	25.0	58.3	16.7
Gumboats and respirator	35	28.6	42.9	28.6
Gumboats and overall	16	50.0	18.8	31.3
Gumboots	5	40.0	20.0	40.0
Gumboots, respirator, Gloves and Waterproof hat	2	50.0	0	50.0
Gumboots, respirator and overall	13	23.1	30.8	46.2
Gumboots, respirator, overall and Gloves	15	26.7	40.0	33.3
Gumboots, overall and Gloves	6	50.0	16.7	33.3
Gumboots overall Goggle Gloves	2	50.0	0	50.0
Mask/ respirator	3	66.7	33.3	0
Gumboots, Mask/ respirator and Gloves	5	40.0	20.0	40.0
overall	2	50.0	0	50.0

Good, fair and bad variable referred to when all worn PPEs protect the applicant completely, protect the applicant completely but have been over used for long time and at least one of the PPE worn were torn/leaking but offered minimal protection

Table 8: Use of PPEs while handling pesticides and their variable score

Activity	Av. duration hectare (Hrs)	Frequency (n)	Variable for the PPE (%)
Activity	Av. duration hectare (Hrs)	Frequency (n)	Good	Fair	Bad
Repair	2	93	29.0	53.8	17.2
Mixing	1	128	18.0	57.8	24.2
Application	3	126	27.0	56.3	16.7
Cleaning the knapsack	½	98	27.6	37.7	34.7

3.4 Farmers Practices on Storage and Disposal of Pesticides leftovers and empty containers

Most farmers disposed chemical remainders by repeat spraying (72.6%), poured on the ground (plate 1) (15.7%) while only 11% disposed in soak pits to empty knapsack (Table 9). Training on safe use of pesticides showed sufficient evidence in contributed to reduced human and environment exposure to pesticides (Table 10). However, none of the responded collected for safe disposal by respective institution such Agrochemicals and Agrochemicals Association of Kenya (AAK).

Table 9: Disposal of chemicals remainders and empty containers

Disposal of empty containers	Percentage (%)	Disposal of chemical remainders	Percentage (%)
Burning	11.2	Pour in a pit latrine	6.1
Bury in the soil	19.6	Pour in disposal pits	5.6
Pit latrine	56.0	Pour on ground	15.7
Leave them in the field	7.0	Re-spraying	72.6
Wash and re-use for home purposes	2.8
Throw in forested area	3.5

Table 10: Relationship between training on safe use of pesticides and disposal of chemical remainders and empty containers

Training	Disposal of empty containers	Percentage (%)	Disposal of chemical remainders	Percentage (%)
Yes	Burning	20.7	Pour in a pit latrine	15.9
	Bury in the soil	37.6	Pour in disposal pits	35.7
	Pit latrine	28.2	Pour on ground	19.6
	Leave them in the field	8.4	Re-spraying	28.9
	Wash and re-use for home purposes	2.7
	Throw in forested area	2.5
No	Burning	11.8	Pour in a pit latrine	7.9
	Bury in the soil	15.5	Pour in disposal pits	4.2
	Pit latrine	39.6	Pour on ground	42.6
	Leave them in the field	5.4	Re-spraying	45.4
	Wash and re-use for home purposes	20.0
	Throw in forested area	7.8

3.5 Self-reported toxicity symptoms and risk factors

Only 9 out of the total number of respondents reported to have or their family member faced toxicity by pesticides. The symptoms included allergies, dizziness, respiratory disorders, headaches and skin irritation/rush. About 78% of the chemical applicants did not enjoy application of pesticides as career but expressed their reasons to continue doing the job (Table 11).

Table 11: Reason provided by the responded for applying chemicals as a career

Reason provided by the responded for applying chemicals as a career	Percentage (%)
Source of income	18.7
Refer it as career	37.8
No other jobs	22.7
Not tiresome job and takes short time	15.3
I have no one to do the work	5.6

3.6 Estimation of exposure to chemicals through modelling for knapsack for one hectare

3.6.1 Pesticides baseline application norms

In both seasons, 20 litre (92.4%) capacity knapsack using high discharge nozzle of 3 to 4 bars (pressure) was the most used in applying pesticides, with 15 (2.2%), 16 (3.2%) and 18 (2.2%) litre size knapsack also documented. Therefore the 20 L capacity knapsack was used in modelling exposure estimation. Farmers observed that, late blight (Phytophthora infestans) was the major (92%) biotic stress followed by weed (6%) and insect (2%) pest. While 14% and 16% of the farmers used insecticides to manage potato pests, merely, 16 % and 3% applied herbicides in the short rain and long rain season respectively. However, 2% of the respondents could not remember the pesticides they applied. These data was in tandem with the pesticides which the respondents purchased (Table 12). Notably, less costly fungicides were the most frequently utilized by the farmers. Seasonal variation contributed to frequency of pesticides application, prices of the chemicals and allied costs. The average cost of applying pesticides per acre was on the range of Kes 600 (short rain) to Kes 1000 (long rain season) which also influenced the frequency of applying the chemical (Figure 7). In addition, about 80% of the respondents stated that, the distance to agrostockist also influenced prices of the pesticides. Pesticide application regimes and patterns of the chemical were as presented in Table 13. Surprisingly, none of the respondent used nor was aware about biologicals. Majority of the chemicals were in class III (harmful) of WHO classification. There was no banned pesticide reported during the study, but one fungicide (Sinik) was not found PCPB registration list.

Unexpectedly, most farmers (about 70%), were unfamiliar with colour codes in the pesticides label which presents hazardous nature of the chemicals prompting on handling safety measures. However, majority of respondents (about 60%) expressed that pictograms on warning signs to use PPEs were easily understood, but more than 50% of the interviewed respondents indicated that pictograms presenting pesticides hazardous looked new to them.

3.6.2 Estimation of exposure level using algorithm

Apparently, majority (about 80%) of the chemicals applied fungicides of different trade name but of similar active ingredient and composition (metalaxyl and mancozeb) to manage potato diseases. These chemicals were applied on average 8 times and 4 times in the short and long rain season respectively (12 times per year) On the other hand insect pest and weeds were mainly managed using Thunder^® (imidacloprid and beta-cyfluthrin) and metribuzin (Figure 7). It was observed that, majority (75%) of farmers used 6 knapsacks which took them 4 to 5 hours to apply fungicides in one hectare. Majority of farmers used only respirator and gumboots combination. Since a number of farmers and chemical applicants observed re-entry period and owing to its complexity in its assessment in an open field situation, the factor was not considered. Cogently, we therefore, sought to estimate the level of exposure using this baseline information.

Table 12: List of pesticides used in potato farming in Nyandarua County

Chemical type	Chemical name	Number of applications per season		Formulation	Active ingredients	WHO Classification
		Short rain	Long rain
Fungicides	Ridomil^®	5	8	solid	Metalaxyl (40 g kg^-1) + Mancozeb (640 g kg^-1)	IV
	Mistress 72^®	4	7	solid	Cymoxanil (80 g kg^-1) + Mancozeb (640 g kg^-1)	III
	Agromax 720	4	8	solid	Cymoxanil (80 g kg^-1) + Mancozeb (640 g kg^-1)	III
	Bigo^®400	2	5	solid	Dimethomorph (200 g kg^-1) + Fluazinam (200g kg^-1)	II
	Equation^®pro	4	6	solid	Famoxadone (225g kg^-1) +Cymoxanil(300 g kg^-1)	III
	Globe 76	2	8	solid	Mancozeb (700 g kg^-1) + Cymoxanil (60 g kg^-1)	III
	Infinito^®	2	4	solid	Fluopicolide 62.5( g L^-1)+Propamocarb 625 ( g L^-1)	III
	Tata Master	3	8	solid	mancozeb 64% + matalaxyl 8%	U
	Matco^®	3	8	solid	Mancozeb (640g Kg^-1) + Metalaxyl (80g Kg^-1)	III
	Milraz^®	4	7	solid	Propineb (700g kg^-1) + Cymoxanil(60g kg^-1)	III
	Revus^®	2	4	Liquid	Mandipropamid 250g litre^-1	III
	Zetanil 76 WP^®	5	7	solid	Mancozeb (700g Kg^-1) + Cymoxanil (60g Kg^-1)	III
	Twigalaxyl^®	4	7	solid	Mancozeb 640g/Kg+ Metalaxyl 80g/Kg	III
	Metacop^®	3	7	solid	Metalayl-M (50 g kg^-1) +Copper oxychloride 400g kg^-1).	III
	Sinik^®	2	7	solid	Unknown	-
Insecticides	Alpha Degree^®	2	1	Liquid	Alpha-Cypermethrin (100g L^-1)	II
	Asta Extrim^®	1	1	Liquid	Acetamiprid (150 g L^-1) +Cypermethrin (50 g L^-1)	II
	Belt^®	1	1	Liquid	Flubendiamide (480 g L^-1)	III
	Duduthrin^®	2	1	Liquid	Lambda-cyhalothrin 17.5g L^-1	II
	Engeo^®	2	1	Liquid	Thiamethoxam 141 g L^-1 + Lambda-cyhalothrin 106 g L^-1	II
Herbicides	Jaguar^®	1	1	Liquid	Bromoxynil 250 g L^-1+ Diflufenican 25 g L^-1	II
	Tata Moto^®	3	5	Liquid	Metribuzin 750 g kg^-1	III
	Tingatinga^®	1	1	Liquid	Triazine 380 g L^-1	III
	Glyweed^®	1	1	Liquid	Glyphosate 380 g L^-1	II
	Sencor^®	4	5	Liquid	Metribuzin 480 g L^-1	II
	Kausha^®	1	1	Liquid	Glyphosate 480 g L^-1	II
	Kickout^®	1	1	Liquid	Glyphosate 480 g L^-1	III

Table 13: Pesticides application norms from the respondents

Pesticide	Application below recommended rate (%)		Application above recommended rate (%)		Recommended rate (%)		Av. knapsacks per hactare
	Short rain	Long rain	Short rain	Long rain	Short rain	Long rain
Ridomil^®	24.5	30.3	28.5	56	47.0	13.7	6
Mistress 72^®	27.6	20.5	10.3	54	62.1	25.5	7
Agromax^®	33.1	18.6	31.0	56.2	35.9	25.2	6
Bigo^®400	0	17.9	67.7	58.6	32.3	23.5	2
Equation^®pro	-	19.2	-	60	-	20.8	4
Globe 76^®	-	12.3	-	56.2	-	31.5	3
Infinito^®	50.1	45.6	11.0	35	38.9	19.4	4
Tata Master^®	20	20	20	50.6	60	29.4	8
Matco^®	-	23.3	-	60.2	-	16.5	6
Milraz^®	33.3	26.4	50.5	61.2	16.2	12.4	3
Revus^®	-	9.6	-	21.4	-	69.0	3
Zetanil 76 WP	25	15.8	55.3	62.5	19.7	21.7	6
Twigalaxyl^®	20.2	12.9	57.3	60.4	22.5	26.7	7
Metacop	-	14	-	58.9	-	27.1	7
Sinik	-	15	-	52.8	-	32.2	4
Downlightor	50	16.2	25.6	65.5	24.4	18.3	5
Alpha Degree	20.5	18.2	40.8	60.2	38.7	21.6	5
Asta Extrim	19.5	14.6	45.2	52	35.3	33.4	4
Belt^®	23.5	16.8	52.3	64.2	24.2	19.0	6
Duduthrin	23.8	17.3	62.1	62.8	14.1	19.9	6
Engeo	33.1	18.1	51.8	56.4	15.1	25.5	5
Jaguar^®	33.4	28.1	52.6	54.2	14.0	17.7	5
Tata Moto^®	25.8	36.0	52.9	58.6	21.3	5.4	6
Tingatinga^®	24.7	21.2	58.7	60.2	16.6	18.6	6
Glyweed^®	25.2	15.1	60.5	48.6	14.3	36.3	6
Sencor^®	31.2	14.3	60.1	46.3	8.7	39.4	6
Kausha^®	31.2	1 9.7	57.3	48.4	11.5	31.9	6
Kickout^®	27.3	15.2	58.2	56.8	14.5	28.0	5

N/A and – represents the pesticide was only applied by one respondent and not applied respectively

To estimate exposure due to fungicide exposure, the overall algorithm described by Fargnoli et al. (2019) was adopted and modified as shown below;

Exposure level of the operator = {(Mixing + Application + Cleaning + Repair) x Skill} per hectare per year)………………………….……………………………………..……..….…….Equation 1

However, we avoided inclusion of PPE, time component and Frequency as proposed by Fargnoli et al. (2019) to avoid possibilities of double counting, instead considered the factors when calculating each of the component. In addition, repair was not considered since most farmers repaired the knapsack before the activity and it had negligible occurrence. Further, we hypothesize that cleaning of knapsack had more weight since chemical applicants did not use gloves. The weights of the exposure components varied and have been published in a number of scientific communications (Butler Ellis et al., 2017; Dick et al., 2010; Ohayo-Mitoko et al., 1999). In the present study, each component was assessed as follows;

a) Mixing (exposure through inhalation and dermal) = (Dose (quantity of pesticide (kg ha^-1) x Time x Frequency of load per day x Concentration of active ingredients x Formulations x Regime (number of sprays in the season) per hectare per year………..…………..……………………………………………………………...………….Equation 2

b) Application (exposure through inhalation and dermal) = (Dose x formulation x duration of application x concentration x application frequency per hectare per year……….……………………….………...………Equation 3

c) Cleaning (exposure through inhalation and dermal) = (Dose x formulation x Regime x concentration x cleaning duration)…..…………………………………………………………………………………………...…......Equation 4

Final decision was based on criteria presented in Table 14 Fargnoli et al. (2019) and data available in the material data sheet and scoring was as presented on Table 15 and .16

Table 14: Exposure levels decision table

Score	Interpretation	Level
< 10	Very low level of exposure	I
10 - 20	Low level of possible exposure	II
21 - 40	Medium low level of exposure	III
41 - 60	High low level of exposure	IV
>61	Very high low level of exposure	V

Table 15: Scoring criteria for factors contributing to exposure of chemical applicants to pesticides

Mixing
Number of loads per day	Score	Formulation	Score	Concentration	Score
1	0.5	Soluble bags	0.5	<50%	0.5
2-5	1	Granules/liquid	1	50-90	1
>5	2	Powder	2	>90	2
Dose (kg ha^-1)	Score	Application Bar scale	Score	Handling frequency	Score
<0.1	1	3	1	<5	0.5
0.1 2.5	2	3 5	2	5 10	1
>2.5	3	5 10	3	10 15	2
		>10	4	15 20	3
Conditions of PPEs		Skills	Score	Time handling chemical (minutes)	Score
Good	0.5	>5	0.25	<1	0.5
Fair	1	1 5	0.5	1-2	1
Bad	2	1	1.0	2-5	2
No PPE	3			5-10	3
				>10	4

Frequency referred to number of applications per year while dose was calculated based on amount of active ingredient per kilogram (from the product label) and then multiplied with the estimated amount required per hectare

With regard to scoring of PPE protection potential, was further broken down into categories described by Dosemeci et al. (2002) since different chemical applicants used different combinations of PPEs which offered varied exposure.

Table 16: PPE scale for the number of PPEs worn

PPE scale	Protection (%)	PPE Score
PPE 0 (did not use PPE)	0	1.0
PPE-1 (worn one of PPEs)	20	0.9
PPE-2 (worn two PPEs	40	0.8
PPE-3 (worn 3 to 4 PPEs)	60	0.7
PPE-4 (at least one PPE missing)	80	0.6

Combined score for PPE-1 & 2, PPE-1 & 3, PPE-2 & 3, PPE-2 & 3 and PPE-1, PPE-2 & 3 was 0.5, 0.4, 0.3 and 0.1 respectively.

Therefore the overall algorithm for PPE was summarized as; PPE score x score for PPE condition in Table 15.

In summary, metalaxyl (40 g kg^-1)and mancozeb (640 g kg^-1) were applied 12 times a year as one product in which 15 knapsacks (with 3 bars pressure) per hectare was used. Chemical applicant took 2 minutes to mix and 8 hours to spray 1 hectare field and used only gumboots and goggles (PPE-2) and with 2 years of spraying experience. Noteworthy, the total amount of product applied per hectare was 2.5 Kg (Dose).

a) Mixing (Metalaxyl and mancozeb) = (metalaxyl dose (40*2.5=0.1 kg) and mancozeb (640 g * 2.5= 1.6 kg) x taking 2 to 3 minutes x Frequency of load (equivalent number of knapsacks per hectare) x Concentration x composition (powder)) per hectare x PPE index x PPE score} frequency per year

Metalaxyl = {(1.0 * 2.0) x 1.0 x 0.5 x 2x (0.8*1.0)} x 2 =3.2

Mancozeb = {(2.0* 2.0) x 1.0 x 1.0 x 2 x (0.8*1)} x 2 =12.8

b) Application (Metalaxyl and mancozeb) = {(metalaxyl dose (40*2.5=0.1 kg) and mancozeb dose (640 g * 2.5= 1.6 kg) x taking 4 5 hours x Frequency of application (6 knapsacks) x Concentration x composition (powder)) per hectare x (PPE index x PPE score)} x frequency per year

Metalaxyl = 1.0 x 4 x 1 x 0.5 x 2.0 x (0.8*1) x 2 = 6.4

Mancozeb = 2.0 x 4 x 1 x 1 x 2 x (0.8*1) x 2 = 25.6

c) Cleaning = {(metalaxyl dose (40*2.5=0.1 kg) and mancozeb dose (640 g * 2.5= 1.6 kg); double diluted, therefore reduced by half x taking 8 minutes x Frequency of cleaning (once) x Concentration x composition (powder)) per hectare x (PPE index x PPE score)} x frequency per year (12 times). Majority of farmers did not use any PPE while cleaning knapsack.

Metalaxyl = {(1.0 * 2.0*½) x 1.0 x 0.5 x 2x (1.0*3)} x 2= 6

Mancozeb = {(2.0* 2.0*½) x 1.0 x 1.0 x 2 x (1.0*3)} x 2 =24

Evaluation of toxicity levels was based on material safety data sheet information and score assigned as showed in Table 17 following improvement of Fargnoli et al., (2019) proposed scale. It should be noted that, the calculations above were based on when the chemical applicants adopted manufacturer’s recommended rate. However, based on Table 13 results, it is apparent that metalaxyl and mancozeb was applied double the rate recommended by the manufacturer (metalaxyl 80 g kg^-1and mancozeb 1280 g kg^-1). Therefore, the implications are showed in Table 18.

Results reveal that, the level of dose in the chemical is very crucial. Exposure to mancozeb had similar weight with when the chemical is mixed with metalaxyl. Ostensibly, exposure to metalaxyl and mancozeb in potato farming was very high and required a high level of intervention (Table 19)

Table 17: Toxicity level and scoring index

Warning statement	WHO colour code	Toxicity index
Extremely hazardous (Class 1a)	Red	5
Very highly hazardous (Class 1b)	Red	4
Highly hazardous (Class II	Yellow	3
Slightly hazardous (Class III)	Blue	2
Unlikely to cause acute hazard in normal use	Green	1

Exposure Risk level was estimated as the multiple of the estimated exposure level with toxicity index (Table 17) and exposure risk based on Table 17 as described by Dosemeci et al., (2002). Table

Table 18: Exposure risk levels and interpretation

Exposure Risk level	Level	Interpretation for level of exposure risk	Interventions
≤ 15	I	Low	Intervention level-1 Awareness of pesticides through mass media Normal trainings programme by extension officers
16 60	II	Mild	Intervention level-2 Update information in the mass media Training targeting framers groups Capacity building for PPE availability
61 150	III	Medium	Intervention level-3 Determine efficacy of chemicals used for alternative sourcing Targeted training (individual farmers) Incentives for PPEs (affordability and access) Biomonitoring tests Non targeted environmental monitoring
≥151	IV	High	Intervention level-4 Replacement of the hazardous chemical Multi-sectoral training interventions co-ordinated by government Supply PPEs free to chemical applicants Medical interventions initiated to prevent/reduce organs damage Targeted environmental monitoring with interventions put in place

Table 19: Summary of exposure from metalaxyl and mancozeb

Parameter	Exposure Levels
Parameter	Metalaxyl at MRR	Metalaxyl double rate	Mancozeb at MRR	Mancozeb double rate	Combined exposure MRR	Combined exposure for double
Mixing	3.2	6.4	12.8	25.6	16.0	41.6
Application	6.4	12.8	25.6	51.2	32.0	83.2
Cleaning	6.0	12.0	24	48	30	78
Exposure level	15.6	31.2	62.4	128.8	76	204.8
Interpretation level	I	III	V	V	V	V
Toxicity index	1	1	2	2	2	2
Exposure risk level	I	III	IV	IV	IV	IV
Interventions proposed	Intervention level-1	Intervention level-3	Intervention level-4	Intervention level-4	Intervention level-4	Intervention level-4

Exposure to chemicals is increasingly becoming an emerging issue globally threatening not only the health of the chemical applicants, but also family members who depend on the applicants as well as consumers of the agricultural products. In the present study, it was apparent that farmers showed a tendency to apply precautions measures while handling pesticides in their farms. Previous studies on exposure assessment have comparable outcomes (Jhalendra et al., 2018; Damalas and Eleftherohorinos, 2011). On the contrary, majority of farmers were aware on the risks associated with pesticides handling. Noteworthy, this is the first study comprehensively conducted in Kenya to the assess pesticides handling in potato production. Pesticides in Kenya are authorised by PCPB under collective principle and understanding that, consumers will read and comply with the instructions on the label. A number of growers perceive that, the language presented in the label is directed to technical and well crop protectionist personnel. Therefore, there is need to pursue a sustainable alternative in providing compelling information to curb the undesirable practices.

Demographic information, suggests farming business was a shared activity between the two genders. However, land ownership was under the control of male gender. Notably, land under cultivation showed a decline trajectory as compared to study conducted by Agong et al. (2021). This could be attributed to increased land subdivision among family members following birth of new affiliates in addition to urbanization. Similarly, Solh and El-fattal (2013) showed that increase in human population threatens land acreage under cultivation. The current study further demonstrates that, education and training of farmers on chemicals handling is a key element in managing pesticides exposure risks. This included reading labels, use of PPEs, checking expiry and registration of the chemical and apt disposal of empty containers and chemical remainders. Correspondingly, Marete et al. (2021) and Mubushar et al. (2019) also conveyed that, literacy level and training prejudiced pesticides exposure risks management. In addition, despite the training and education, unexpectedly fewer respondents ignored the deterrents practices. Contrariwise, Viviana et al. (2007) study suggested that, education did not play any significant role in adhering to precautionary measures. This could be attributed to labels which are less attractive, small sized font, visual acuity, technical information, cognitive reading ability and too long information without clear guidelines as proposed by (Viviana et al., 2007; Grey et al., 2005). Similar findings were reported in the United Kingdom where 54% of the chemical handlers read the labels but did not comply with the instructions (Jhalendra et al., 2018). Most farmers relied on the first point of contact (agrostockist) for instructions on use and safety measures However, farmers and chemical applicants elucidated that, access to training institution was a major challenge.

Majority (93%) of farmers were in the cognizant that pesticides are unavoidable in crop production owing to their efficacy in managing biotic and abiotic stresses. On the contrary, the respondents expressed that, chemicals pose hazards to human and environment. Non-chemical options were not recorded as preference to chemical pesticides among the respondents to manage biotic and abiotic stresses. This indicated there was no mitigation measure to manage pesticides risks while type of pesticide to treat pathologies. Lack of efficacious alternative was cited as the major reason for dependence on chemical pesticides and require more applications. Indeed, studies conducted by Kilonzi et al. (2020) and (Yao et al., 2016) suggested that, though biological products were eco-friendly, they do not offer effective measures.. One of the suitable solution against risks associated with pesticides to human, is availing affordable protective clothing. On the other hand, a number of chemical applicants were able to discriminate the role of PPEs to manage risks allied to the chemicals. However, this was not the case, a vast number of chemical applicants reported that affordability and availability of PPEs at agrostockist were the major constrain. This could be the root course predisposing chemical applicants to pesticides exposure. Similar proponents were reported by Vercruysse et al. (1999).

As a requirement by law in Kenya, it is mandatory for all chemical companies to provide material safety data sheet for the chemicals produced. Despite this effort, majority of farmers comprehended with the meaning of skull and cross bones, but about half the respondents interpreted the meaning of colour codes; toxicity indicators based on WHO classification. The colour codes interpret information based on toxicity index of the chemical to warn on the use of protective gears. Moreover, pesticides were stated to be frequently stored primarily in the living house. Previous work has showed that, chemicals stored indoors increases chances of exposure risks, accidents through suicides, children poisoning as well food products contamination (Jensen et al., 2011). Many people disposed chemical remainders by repeat spraying to empty the knapsack which in addition to washing and disposing the wash off predisposed the environment to contamination. Studies have showed chemical spillage is one of the major cause for soil degradation (Lo, 2010). Unfortunately, majority of respondents were for the view that, information on disposal was not provided in the label. This raises public health concerns, since label is the primary source of information for reducing exposure risks.

In potato value chain, the current study and previous studies (Oyoo et al., 2021) revealed that late blight was the major biotic stress affecting the crop. In response, majority of chemicals reported in our study were to manage this disease. The choice of which fungicide to frequently use was based on price tag. It was also noted that, the use herbicides is on rise by 25% as compared to our previous unpublished survey (Kilonzi et al., 2019) possibly it is becoming cheaper input cost as compared to manual labour. Notably, a significant greater number of farmers applied metalaxyl and mancozeb extensively than any other chemicals in the market to manage late blight. Studies on late blight have suggested that fungicides are applied up to 10–15 times per cropping season depending on weather conditions (Taylor et al., 2013). Overuse of the chemicals pose health risks arising from residues in food and drinking water (Lopes et al., 2009; Atmaca et al., 2018)). Mancozeb is non-systemic preventive fungicide (Gullino et al., 2010) usually broken down by plant to Carbon disulphide which accumulate in potato leaves and in pericardial layer of tubers if extensively applied (Alam et al., 2012). The molecule is carcinogenic and antithyroid compound (ethylenethiourea) when exposed to light (Panganiban et al., 2004). Prolonged exposure to mancozeb is associated with dermatitis and eye problems (Cole et al., 1997) and hence pose threats to occupational workers (Wesseling et al., 2005). Recently Kim (2017) reported that prolonged exposure to carbamates resulted in asthma and chronic problems including cancer. On the other side, metalaxyl also implicate on human health. Abass et al. (2007) reported that metalaxyl affects liver functionalities whilst Zhang et al. (2017) found that the chemical influence breast cancer progression. From our current study, it was evident that, exposure to this chemicals exceeded limit of acceptable exposure. It is worth noting that, concentration of active ingredient plays a key role in exposure. Mancozeb concentration (64%), was higher than metalaxyl (4%), and therefore the later had significant effect on exposure level than the former. It is therefore pertinent to contemplate pesticides risks perception among users in assessment process and respective policy development.

Survey results revealed that a number of the farmer mixed insecticide (Thunder®) two times with fungicides during the cropping season. This provides insights that the exposure level to chemicals is very high in potato production. Further work is needed to study toxicological (biomonitoring) and epidemiology effects of mixed chemicals. Additionally, studies on environmental effects resulting from spillage and cleaning of chemical applicators is necessary.

Imprudent use of pesticides in most developing countries including Kenya constitutes one of the main public health concerns owing to the dependence on agricultural farming as key economies. To reduce environmental and health risks attributed to chemicals, pesticides label is expected to be the primary source of product message, unfortunately this is not always the situation. The survey revealed that, the level of education and training played a key role in managing risks associated with pesticides. Demographic data showed that land was majorly owned by male gender. Only a few chemical applicants used full PPE kit and read chemical label instructions. However, a number of the chemical applicants interviewed could read chemical labels but did not follow instructions including rate of chemical instruction and was regarded as ignorance. Metalaxyl and mancozeb were widely used to manage late blight, imidacloprid and beta-cyfluthrin (Thunder®) to control insect pest and metribuzin to manage weeds. The chemicals were applied at double rate the manufactured rate. Observation of precaution measures including adhering to chemical instructions was low. However, majority of farmers and chemical applicants, were awareness of risks associated with pesticides. Estimation of exposure level showed that, farmers are at high risk. Even though, exposure to insecticides mixed with the fungicides was not considered in the model, it was apparent that, chemical applicants were at the highest level of exposure. This provides insights on the need for intervention to reduce the risks which may result in chronic illness.

ACKNOWLEDGEMENT

We acknowledge the contribution of Centre Director, KALRO Tigoni for providing funds and transport facilitations and Swedish International Development Agency (SIDA) through Mats Forkman of Swedish Chemical Agency (KEMI) staff, Sweden for training support on the project. Much appreciation to David Githui (staff at KALRO Tigoni) for assisting in questionnaire development. I thank farmers of Nyandarua County for their cooperation.

Funding

The study was funded by KALRO Tigoni through Centre Revolving Fund, while training was funded by Swedish International Development Agency (SIDA) through Swedish Chemical Agency (KEMI), Sweden.

Contributions of Authors

Jackson Mutuku Kilonzi: conducted the study and authored paper

Moses Nyongesa Wamboba: participated in the study, budgetary and revision of the paper

Nancy Ng’ang’a: preparation of questionnaire and participation in the study

Statements and declarations

Data analysed during the study is under the custody of corresponding author and can be availed on request

Conflict of interest

We declare that this manuscript has no conflict of interests

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Plate 1 is available in the Supplementary Files section.

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Plate 1: Photo a, b and c shows chemical applicant pouring chemical reminder (a), washing knapsack (b) and chemical spilled onto soil an example encountered during the survey

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Pesticides Handling, Risk Management and Estimation of Exposure Levels in Potato Farming Under Small Scale Production

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Abstract

Figures

1 INTRODUCTION

2 MATERIALS AND METHODS

2.1 Questionnaire development

2.2 Data analysis

3 RESULTS

3.1 Demographic and profile characteristics of the potato farmers

3.2 Knowledge and understanding of pesticides handling among farmers

3.3 Farmers Knowledge on Pesticide Risk Awareness and Management

3.4 Farmers Practices on Storage and Disposal of Pesticides leftovers and empty containers

3.5 Self-reported toxicity symptoms and risk factors

3.6 Estimation of exposure to chemicals through modelling for knapsack for one hectare

3.6.1 Pesticides baseline application norms

3.6.2 Estimation of exposure level using algorithm

4 DISCUSION

5 CONCLUSIONS

Declarations

References

Plate

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