Table 1, Table 2 and Table 3 display the results of metal analysis in both types of feathers under study and then mean metal concentrations were compared (Table 4).
Lead (Pb) is the ubiquitous toxic metal present in low concentrations in the environments. Lead can originate from natural sources such as volcanos, erosion, disasters, ceramic industries and food industries.
In Figure 2 highest and lowest concentrations of lead were found at Jalandhar Bypass, Ludhiana. This is due to the air pollutants coming from vehicles emission and from the burning of fossil fuels. In washed feathers, collected at Jalandhar bypass, Agronomy farm PAU Ludhiana, Mullanpur, Jalandhar FCI, Hoshiarpur FCI has average contents of lead as 0.730, 0.104, 0.135, 0.121 and 0.394, respectively (Table 2). Mean lead concentration at Jalandhar bypass, Ludhiana (0.730 ppm) was significantly higher compared to rest of the locations and lowest was recorded at Agronomy farm, PAU (0.104 ppm).
Similalry, in unwashed samples of Jalandhar bypass, Ludhiana showed higher concentrations of lead with an average content of 1.2 ppm and lowest was recorded at Agronomy farm, PAU (0.200 ppm) and Jalandhar FCI (0.200 ppm) (Table 3). No significant difference in average lead concentrations was found at the Agronomy farm, Ludhiana and in Jalandhar FCI, which is due to less concentration of this metal in both the locations.
Tsuji et al. (2002) determined lead concentrations for several bird species in a heavily hunted region of Canada reported a range of lead concentrations more than 20 ug/g which indicates toxicity of lead in wild mallard ducks.
A study conducted by Kim et al. (2007) on two species of heron to study the metal concentration in feathers reported that lead concentration were different in two heron species. While studying the feathers of small birds in Punjab, India, Bianchi et al (2008) discovered that lead concentrations are directly linked to feather exposure time. As a result, unwashed feathers are the most reliable indicator of lead levels in the water and soil.
Sani et al (2019) conducted a study for the assessment of heavy metals in feather of birds reported highest concentration of lead followed by cadmium, chromium and manganese. So higher concentration of lead in unwashed feathers in Jalandhar bypass not only show the pattern of lead deposition but a way to monitor lead levels in the environment through feathers.
Cadmium (Cd) is contained in the atmosphere in very low concentrations. In washed feathers (Table 2), the concentrations were 0.005, 0.018, 0.0055, 0.025 and 0.017 ppm, respectively at Agronomy farm Ludhiana, Jalandhar bypass, Mullanpur, Jalandhar FCI and Hoshiarpur FCI. The highest cadmium concentration was recorded at Jalandhar bypass (0.18 ppm) and Hoshiarpur FCI (0.17 ppm) which were also statistical at par with each other.
Similalry, at Agronomy farm PAU, Jalandhar bypass Ludhiana, Mullanpur, Jalandhar FCI and Hoshiarpur FCI, the average levels of Cd were 0.01, 0.3, 0.01, 0.004 and 0.2 ppm in unwashed feathers. The highest concentration of cadmium in unwashed feathers was found at Jalandhar bypass (0.300 ppm) and Hoshiarpur FCI (0.200 ppm) (Table 3; Fig. 2), which is due to vehicular pollution and a number of factories in the region, resulting in higher levels of cadmium in the atmosphere. So, pigeons in urbanized areas are more contaminated as compared to rural ones (Nam and Lee 2006).
Jayakumar et al (2011) demonstrated metal pollution in six bird’s species, reported that level of cadmium was less than 1 ug/g in four species with significant variation (p greater than 0.05) with exception in Jungle Babbler and Common Myna.
Chromium (Cr) is a vital element that can be present in trace amounts in the world. High chromium concentrations in animal tissue are due to agricultural activities, anthropic activities such as the production of bricks and emissions from vehicles (Movalli 2000). Our study showed low chromium levels in the washed feathers compared to unwashed feathers, with higher chromium levels at Hoshiarpur FCI (Tables 2 and 3). Figure 2 shows the order of mean concentartions respectively Hoshiarpur FCI> Jalandhar bypass> Mullanpur> Jalandhar FCI> Agronomy farm, which can be explained by TPS accumulation in urbanised bird feathers. This demonstrates that chromium exposure in covered or less urbanised areas comes from the animals' diet.
Muralidharan (2018) reported higher level of chromium, magnesium and iron in the feathers of young house sparrow residing in Mumbai city, India.
Sahu et al (2019) revealed high chromium concentration that is 1.819 ppm in the feathers of pigeons (C. livia) at one site as compared to other selected sites at Ajmer city, Rajasthan.
Arsenic is a trace element found in the environment and in the living beings. It is released into environment through agricultural practices including the application of fertilizers and pesticides. The mean concentration of As at Hoshiarpur, Jalandhar FCI, Agronomy farm, cold storage Jalandhar bypass, cold storage Mullanpur, Ludhiana was 0.014 ppm, 0.004ppm, 0.008 ppm, 0.033, 0.01 ppm in washed feathers and was 0.02, 0.005, 0.009, 0.05 and 0.03 ppm in unwashed feathers, respectively.
Wiemeyer et al. (1980) studied about the concentration in the four species of owls and the highest concentration found among them was 0.40 ± 0.30 mg/kg, that is lower than the concentration of 5 mg/kg found in the USA in an area of possible As pollution. Very limited studies were there to use the feathers for quantification of arsenic, which makes it difficult to determine whether the amount of As recorded is significant or not (Burger et al. 2015).