3.1Profile of the participants
A total of 1,006 questionnaires with serum information were collected. Among them, 544 participants were boys (54.1%), and 462 were girls (45.9%). The numbers of children from grade 1 to grade 3 (45%) and from grade 4 to grade 6 (33.9%) in primary school were top two, and the number of children aged 5-6 were the least (4%), details was shown in Table 1.
Table 1. Sociodemographic characteristics of the participants.
Characteristics
|
Subjects Number
(Percentage)
|
NP
|
DMP
|
BPA
|
25th
|
50th
|
75th
|
25th
|
50th
|
75th
|
25th
|
50th
|
75th
|
Gender
|
|
|
|
|
|
|
|
|
|
|
Male
|
544(54.1)
|
42.88
|
45.42
|
48.92
|
26.02
|
28.13
|
33.98
|
23.44
|
27.57
|
33.60
|
Female
|
462(45.9)
|
42.69
|
45.13
|
48.79
|
25.86
|
28.76
|
36.73
|
24.05
|
27.44
|
33.81
|
Grade
|
|
|
|
|
|
|
|
|
|
|
Preschool
|
25(2.5)
|
41.00
|
43.15
|
48.38
|
27.29
|
28.91
|
47.44
|
23.64
|
25.79
|
34.61
|
Grade 1-3
|
453(45.0)
|
42.71
|
45.20
|
48.55
|
25.81
|
28.63
|
36.04
|
23.47
|
27.41
|
32.91
|
Grade 4-6
|
341(33.9)
|
42.91
|
45.20
|
48.99
|
25.72
|
28.14
|
33.46
|
23.31
|
26.35
|
32.87
|
Grade one of
junior high school
|
187(18.6)
|
42.50
|
45.28
|
48.87
|
26.23
|
28.47
|
35.46
|
24.64
|
29.30
|
36.82
|
Age
|
|
|
|
|
|
|
|
|
|
|
5-6 years old
|
40(4.0)
|
42.37
|
45.90
|
55.58
|
26.42
|
29.63
|
40.44
|
21.90
|
25.79
|
35.13
|
7-8 years old
|
334(33.2)
|
42.67
|
45.07
|
47.90
|
25.44
|
27.90
|
35.98
|
23.56
|
26.68
|
31.99
|
9-10 years old
|
261(25.9)
|
43.76
|
45.67
|
50.16
|
25.97
|
28.63
|
34.17
|
23.47
|
27.12
|
32.91
|
11-12 years old
|
218(21.7)
|
42.75
|
45.20
|
48.79
|
25.83
|
28.25
|
33.46
|
24.07
|
27.17
|
33.99
|
13-14 years old
|
153(15.2)
|
42.48
|
45.21
|
48.48
|
26.23
|
28.24
|
35.34
|
24.67
|
28.72
|
37.08
|
Address for children
|
|
|
|
|
|
|
|
|
|
|
Huichuan District (industrial zone)
|
282(28.0)
|
45.09
|
50.29
|
53.15
|
26.36
|
30.60
|
48.28
|
24.65
|
29.91
|
44.65
|
Honghuagang District (residential zone)
|
414(41.2)
|
42.52
|
44.71
|
46.98
|
25.75
|
28.19
|
33.98
|
24.45
|
28.54
|
33.53
|
Bozhou District (suburb)
|
310(30.8)
|
42.04
|
43.87
|
45.93
|
25.72
|
27.90
|
30.29
|
22.19
|
25.96
|
28.74
|
Decoration times
|
|
|
|
|
|
|
|
|
|
|
Undecorated
|
611(60.7)
|
42.50
|
45.20
|
48.89
|
25.97
|
28.23
|
35.19
|
23.44
|
27.12
|
32.91
|
Decoration 1-3 times
|
395(39.3)
|
43.00
|
45.28
|
48.55
|
25.84
|
28.47
|
35.22
|
24.07
|
28.64
|
35.04
|
Feeding pattern
|
|
|
|
|
|
|
|
|
|
|
Pure breast milk
|
494(49.1)
|
42.53
|
45.18
|
49.14
|
26.01
|
28.44
|
36.09
|
24.40
|
27.47
|
33.58
|
Mainly breast milk, supplemented by milk powder
|
260(25.8)
|
42.43
|
44.75
|
48.38
|
26.06
|
28.21
|
34.17
|
23.82
|
28.05
|
33.99
|
Milk powder feeding is the main method, supplemented by breast-feeding
|
113(11.2)
|
43.87
|
45.89
|
48.79
|
25.83
|
28.50
|
33.55
|
21.91
|
25.97
|
30.26
|
Milk feeding only
|
139(13.8)
|
43.75
|
45.67
|
49.13
|
25.72
|
27.30
|
32.06
|
23.64
|
27.92
|
35.90
|
Frequency of perms used during pregnancy
|
|
|
|
|
|
|
|
|
|
|
0
|
973(96.7)
|
42.71
|
45.20
|
48.79
|
25.92
|
28.22
|
34.83
|
23.67
|
27.57
|
33.99
|
1-2 times
|
33(3.3)
|
45.11
|
47.12
|
50.39
|
26.92
|
34.17
|
55.73
|
22.47
|
24.44
|
29.50
|
Frequency of hair gels used during pregnancy
|
|
|
|
|
|
|
|
|
|
|
0
|
930(92.4)
|
42.67
|
45.20
|
48.75
|
25.92
|
28.27
|
35.15
|
23.67
|
27.47
|
33.60
|
Several times
|
76(7.6)
|
43.35
|
45.88
|
49.73
|
26.11
|
28.72
|
35.50
|
22.81
|
27.89
|
34.08
|
Frequency of cosmetics used during pregnancy
|
|
|
|
|
|
|
|
|
|
|
0
|
894(88.9)
|
42.69
|
45.18
|
48.79
|
25.86
|
28.44
|
35.22
|
23.67
|
27.47
|
33.68
|
1-2 times
|
111(11.1)
|
42.99
|
46.04
|
49.04
|
26.02
|
27.09
|
35.00
|
23.12
|
27.89
|
33.94
|
Frequency of using plastic lunch box during pregnancy
|
|
|
|
|
|
|
|
|
|
|
1 to 3 times each day
|
11(1.1)
|
42.14
|
43.62
|
44.58
|
27.62
|
28.63
|
34.78
|
21.77
|
28.23
|
39.28
|
3 to 10 times a month
|
16(1.6)
|
43.79
|
45.92
|
52.86
|
26.57
|
26.92
|
33.68
|
23.41
|
26.77
|
34.08
|
3 to 10 times a year
|
451(44.8)
|
42.88
|
45.31
|
48.72
|
25.74
|
28.33
|
36.05
|
23.62
|
27.57
|
33.55
|
Never
|
528(52.5)
|
42.69
|
45.21
|
49.14
|
26.23
|
28.27
|
34.15
|
23.70
|
27.47
|
33.73
|
Frequency of plastic water cup used during pregnancy
|
|
|
|
|
|
|
|
|
|
|
Daily
|
7(0.7)
|
41.20
|
43.83
|
47.72
|
26.36
|
27.65
|
70.51
|
28.85
|
29.57
|
42.57
|
Often
|
525(52.2)
|
42.95
|
45.69
|
49.14
|
25.92
|
28.16
|
35.44
|
23.67
|
27.47
|
33.60
|
Occasionally
|
182(18.1)
|
42.43
|
45.21
|
47.27
|
26.03
|
29.08
|
34.38
|
22.36
|
28.30
|
33.99
|
Never
|
292(29.0)
|
42.50
|
44.85
|
48.38
|
25.81
|
28.59
|
34.73
|
23.60
|
27.10
|
33.27
|
Types of domestic drinking water
|
|
|
|
|
|
|
|
|
|
|
Commercial bucketed water
|
865(86.0)
|
42.69
|
45.18
|
48.72
|
25.83
|
28.23
|
35.32
|
23.67
|
27.47
|
33.99
|
Well water
|
20(2.0)
|
43.62
|
45.51
|
47.10
|
26.64
|
28.03
|
34.78
|
24.44
|
29.39
|
30.78
|
Boiled tap water
|
49(4.9)
|
42.52
|
46.58
|
50.81
|
26.19
|
28.54
|
33.17
|
23.48
|
27.27
|
31.85
|
Commercial bottled water
|
9(0.9)
|
41.23
|
44.83
|
46.57
|
25.71
|
26.58
|
90.37
|
25.29
|
33.55
|
51.00
|
Mountain spring water
|
30(3.0)
|
44.84
|
46.20
|
49.45
|
26.74
|
31.08
|
36.39
|
25.96
|
29.81
|
36.82
|
Other
|
33(3.3)
|
43.46
|
45.50
|
51.65
|
27.31
|
28.13
|
33.87
|
21.42
|
26.23
|
30.75
|
Frequency of pacifiers used
|
|
|
|
|
|
|
|
|
|
|
Occasional used
|
218(21.7)
|
42.95
|
45.55
|
48.38
|
25.77
|
27.78
|
33.73
|
23.56
|
30.01
|
36.42
|
Often used
|
67(6.7)
|
42.61
|
45.88
|
49.73
|
26.05
|
31.76
|
37.40
|
26.35
|
32.13
|
45.75
|
Never used
|
721(71.7)
|
42.70
|
45.18
|
48.90
|
25.97
|
28.47
|
35.15
|
23.47
|
26.99
|
32.69
|
Numbers of plastic toys
|
|
|
|
|
|
|
|
|
|
|
None
|
41(1.1)
|
42.33
|
43.96
|
46.90
|
25.74
|
27.69
|
36.41
|
23.17
|
28.92
|
38.27
|
≤ 10 pieces
|
135(13.4)
|
43.01
|
45.71
|
49.63
|
25.67
|
29.61
|
35.34
|
22.49
|
26.70
|
29.57
|
≤ 50 pieces
|
300(29.8)
|
42.88
|
45.36
|
48.89
|
25.97
|
28.63
|
36.12
|
23.82
|
26.93
|
31.34
|
≤ 100 pieces
|
321(31.9)
|
42.67
|
45.21
|
48.79
|
25.86
|
27.80
|
34.17
|
23.61
|
27.81
|
33.53
|
>100 pieces
|
209(20.8)
|
42.74
|
45.81
|
49.15
|
26.02
|
28.52
|
34.60
|
24.07
|
30.26
|
40.45
|
Materials for food storage
|
|
|
|
|
|
|
|
|
|
|
No microwave
|
638(63.4)
|
42.48
|
44.75
|
47.67
|
25.68
|
27.96
|
33.02
|
23.79
|
27.93
|
35.89
|
Chinaware
|
317(31.5)
|
42.32
|
44.65
|
48.31
|
25.79
|
27.96
|
32.38
|
24.51
|
28.12
|
34.84
|
Heat-resistant plastics
|
19(1.9)
|
43.35
|
46.66
|
49.93
|
25.57
|
26.82
|
29.08
|
26.70
|
31.33
|
47.07
|
Heat-resistant plastic wrap
|
13(1.3)
|
43.85
|
46.34
|
50.77
|
25.55
|
26.91
|
32.26
|
23.42
|
29.50
|
39.17
|
Aluminum foil
|
19(1.9)
|
42.70
|
44.13
|
46.70
|
25.24
|
26.74
|
33.07
|
25.55
|
30.09
|
34.55
|
Frequency of hair dyes used by children
|
|
|
|
|
|
|
|
|
|
|
Never
|
980(97.4)
|
42.75
|
45.26
|
48.91
|
25.92
|
28.33
|
35.34
|
23.61
|
27.47
|
33.73
|
1-2 times
|
26(2.6)
|
41.83
|
44.36
|
47.05
|
25.97
|
27.96
|
33.22
|
24.56
|
28.30
|
35.20
|
Frequency of hair spray and perfume use for children
|
|
|
|
|
|
|
|
|
|
|
Never
|
737(73.3)
|
42.70
|
45.18
|
48.53
|
25.93
|
28.30
|
35.34
|
23.71
|
27.89
|
33.99
|
1-2 times
|
267(26.7)
|
42.87
|
45.31
|
49.32
|
25.92
|
28.22
|
35.00
|
23.31
|
26.66
|
33.21
|
Frequency of nail polish and cosmetics used by children
|
|
|
|
|
|
|
|
|
|
|
Never
|
703(69.9)
|
42.51
|
45.06
|
48.75
|
25.93
|
28.22
|
35.76
|
24.11
|
28.22
|
35.18
|
1-2 times
|
301(30.1)
|
42.99
|
45.52
|
48.82
|
25.92
|
28.50
|
33.67
|
22.81
|
26.28
|
31.51
|
Frequency of plastic tableware used by children
|
|
|
|
|
|
|
|
|
|
|
Never
|
356(35.4)
|
42.43
|
44.73
|
49.45
|
26.20
|
28.35
|
35.34
|
22.95
|
27.35
|
33.53
|
1-3 times in a period of 1-3 months
|
592(58.8)
|
42.99
|
45.51
|
48.89
|
25.84
|
28.13
|
34.71
|
24.16
|
27.47
|
33.73
|
≥ 10 times in one month
|
58(5.8)
|
42.70
|
45.46
|
48.25
|
26.92
|
30.34
|
37.56
|
26.06
|
30.54
|
43.04
|
Frequency of fish and shellfish intake in children
|
|
|
|
|
|
|
|
|
|
|
Daily
|
10(1.0)
|
43.18
|
47.05
|
48.07
|
25.57
|
25.81
|
34.75
|
22.60
|
24.95
|
40.73
|
Once to three times a week
|
294(29.2)
|
42.98
|
45.42
|
48.39
|
25.69
|
27.29
|
32.98
|
24.64
|
28.45
|
39.06
|
Occasionally several times a year
|
626(62.2)
|
42.48
|
45.18
|
49.08
|
26.14
|
28.60
|
35.34
|
23.50
|
27.41
|
31.32
|
Never
|
76(7.6)
|
43.37
|
45.90
|
48.83
|
25.97
|
28.54
|
42.25
|
23.44
|
26.50
|
34.48
|
Update frequency of plastic toys
|
|
|
|
|
|
|
|
|
|
|
Weekly
|
119(11.8)
|
44.09
|
47.25
|
50.31
|
26.87
|
29.08
|
34.50
|
25.50
|
31.34
|
40.50
|
Monthly
|
90(8.9)
|
42.30
|
44.74
|
49.04
|
25.94
|
30.93
|
40.79
|
23.14
|
29.36
|
40.31
|
Half a year
|
343(34.1)
|
42.82
|
45.18
|
47.27
|
25.77
|
28.21
|
37.09
|
23.62
|
28.35
|
34.03
|
Each year
|
430(42.7)
|
42.73
|
45.21
|
49.14
|
25.83
|
28.05
|
33.45
|
23.67
|
26.53
|
30.13
|
Never
|
24(2.4)
|
42.33
|
45.15
|
47.10
|
26.49
|
28.13
|
35.34
|
22.01
|
27.85
|
38.27
|
Duration of children birth
|
|
|
|
|
|
|
|
|
|
|
Premature infant
|
80(8.0)
|
43.00
|
46.00
|
49.01
|
26.26
|
27.96
|
35.48
|
21.55
|
25.08
|
29.66
|
Late delivery infant
|
32(3.2)
|
42.30
|
44.36
|
48.58
|
25.83
|
27.44
|
30.62
|
25.29
|
29.91
|
32.61
|
Full-term
|
894(88.9)
|
42.70
|
45.20
|
48.75
|
25.92
|
28.44
|
35.34
|
23.82
|
27.63
|
35.14
|
Materials for baby bottle or cup
|
|
|
|
|
|
|
|
|
|
|
Glass
|
529(52.6)
|
42.48
|
45.21
|
48.89
|
25.92
|
28.44
|
35.10
|
23.62
|
27.28
|
33.60
|
Silica gel
|
70(7.0)
|
43.74
|
45.91
|
50.39
|
25.96
|
27.35
|
30.78
|
24.35
|
28.54
|
32.72
|
Plastic
|
252(25.0)
|
43.09
|
45.36
|
47.77
|
25.72
|
28.02
|
34.78
|
24.17
|
27.57
|
32.13
|
Stainless steel
|
147(14.6)
|
42.73
|
45.65
|
49.63
|
26.25
|
28.91
|
37.12
|
22.07
|
27.63
|
36.59
|
Other
|
8(0.8)
|
42.18
|
42.51
|
45.42
|
29.46
|
40.00
|
48.56
|
32.91
|
42.94
|
76.69
|
Whether exposed to pesticides
|
|
|
|
|
|
|
|
|
|
|
Yes
|
38(3.8)
|
43.38
|
46.01
|
47.73
|
25.41
|
27.80
|
31.40
|
21.99
|
25.96
|
35.20
|
No
|
968(96.2)
|
42.70
|
45.24
|
48.89
|
25.93
|
28.33
|
35.34
|
23.69
|
27.57
|
33.60
|
Parent occupation classification
|
|
|
|
|
|
|
|
|
|
|
Government companies
|
139(13.8)
|
42.65
|
45.18
|
48.52
|
25.80
|
28.14
|
31.95
|
24.75
|
27.29
|
37.48
|
Medical related occupation
|
43(4.3)
|
43.96
|
45.88
|
48.07
|
26.19
|
28.13
|
34.17
|
21.64
|
26.66
|
31.55
|
Free small business (catering, service, etc.)
|
307(30.5)
|
42.73
|
45.52
|
49.63
|
25.84
|
28.04
|
35.34
|
24.16
|
28.19
|
33.66
|
Migrant Workers
|
45(4.5)
|
43.74
|
45.71
|
49.45
|
25.59
|
27.78
|
33.99
|
22.51
|
25.12
|
29.22
|
Farming
|
72(7.2)
|
42.01
|
43.76
|
46.80
|
26.11
|
30.62
|
42.30
|
22.40
|
26.06
|
29.27
|
Education related
|
43(4.3)
|
43.62
|
45.89
|
48.41
|
27.66
|
32.30
|
36.13
|
25.96
|
29.39
|
33.53
|
Others
|
357(35.5)
|
42.75
|
45.04
|
48.75
|
25.97
|
28.76
|
35.34
|
23.68
|
27.47
|
34.62
|
Ways to plastic products
|
|
|
|
|
|
|
|
|
|
|
Drinking utensils, cups
|
161(16.0)
|
42.71
|
45.42
|
48.25
|
25.81
|
28.10
|
32.18
|
23.01
|
27.27
|
32.13
|
Containers for meals, snacks, fruits, etc.
|
83(8.3)
|
43.76
|
45.91
|
49.37
|
26.25
|
28.54
|
43.24
|
24.11
|
26.65
|
31.80
|
Plastic toys (LEGO etc.)
|
254(25.2)
|
42.32
|
44.74
|
47.72
|
25.39
|
27.36
|
34.78
|
24.16
|
28.30
|
33.35
|
Small household items (toothbrushes, plastic bags, plastic wrap, etc.)
|
355(35.3)
|
42.88
|
45.24
|
49.14
|
26.42
|
28.72
|
36.53
|
23.62
|
27.80
|
36.59
|
School supplies
|
129(12.8)
|
43.42
|
46.05
|
49.30
|
25.72
|
28.23
|
33.98
|
22.68
|
25.96
|
31.28
|
Others
|
24(2.4)
|
43.02
|
45.20
|
48.07
|
26.49
|
28.13
|
34.17
|
25.10
|
30.28
|
42.41
|
3.2 Standard curve and concentration of NP, BPA and DMP
The NP, BPA and DMP standard solutions were calibrated by HPLC, and the results of linear regression equation were calculated (Supplementary Table 2) . The correlation coefficient of these linear regression equations were ≥ 0.999. NP concentration was around 40.72 - 77.03 ng/ml, with an average of 45.85 ng/ml; BPA concentration was about 14.15 - 216.12 ng/ml, with an average of 26.31 ng/ml; and DMP concentration was around 22.51-132.07 ng/ml, with an average of 31.62 ng/ml.
3.3 Comparison of the concentrations of NP, BPA and DMP in serum by address, gender and age
There was significant difference in the serum concentrations of NP, BPA, DMP in school-age children in Huichuan District (industrial zone), Honghuagang District (residential zone) and Bozhou district (suburb) (FNP = 548.961, PNP < 0.001,FBPA = 189.198,PBPA < 0.001, FDMP = 112.476, PDMP< 0.001). The serum concentrations of NP (P< 0.001), BPA (P< 0.001), DMP (P < 0.001) in school-age children in industrial zone were higher than those in residential zone and suburb. The average concentration of NP in boys was 45.97 ± 4.50 μg/ml, and in girls was 45.71 ± 4.42 μg/ml; the average concentration of BPA in boys was 31.29 ± 11.08 μg/ml, and in girls was 28.00 ± 11.87 μg/ml; the average concentration of DMP in boys was 31.91 ± 12.53 μg/ml, and in girls was 33.28±15.61 μg/ml. There was no significant gender difference in the concentration between boys and girls (Figure 4 and Supplementary Table 2). The results analysis showed in Supplementary Figure 2.
3.4 Correlation between serum EDCs (NP, BPA and DMP) concentrations and environmental risk factors
NP, BPA, and DMP concentrations in serum were used as dependent variables, and the environmental risk factors on the questionnaire were used as independent variables. The environmental risk factors that affected NP, BPA, and DMP concentrations in serum were analyzed by multiple linear regression.
The regression coefficients of hair gels used during pregnancy (P = 0.012), types of domestic drinking water (P< 0.001), nail polish and cosmetics used by children (P< 0.001) were positive, indicating that these three factors were significantly positively correlated with NP concentration (Figure 5A). The other seven factors, including gender (P = 0.004), feeding pattern (P = 0.047), plastic water cup used during pregnancy (P = 0.042), hair spray and perfume use for children (P = 0.019), duration of children birth (P = 0.002), materials for baby bottle or cup (P = 0.002) and ways to plastic products (P = 0.034) were significantly positively correlated with BPA concentration, indicating that these environmental factors could increase BPA concentration in serum in in school-age children (Figure 5B). Gender (P = 0.038), perms used during pregnancy (P < 0.001 ), hair spray and perfume use for children (P = 0.012), using plastic lunch box during pregnancy (P = 0.007), duration of children birth (P = 0.006), exposure to pesticides (P = 0.008), parents’ occupations (P = 0.041) were positively correlated with DMP concentrations, indicating that these environmental factors could increase DMP concentrations in children's serum (Figure 5C).
3.5 Correlations between serum EDCs (NP, BPA and DMP) concentrations and hepatic function
3.5.1 Effects of EDCs on serum TBIL level
Binary logistic regression analysis of data showed the associations of serum DMP (OR: 1.371 , 95% CI: 1.038 -1.811, P = 0.026) and NP (OR: 1.344 , 95% CI: 1.019 -1.772, P = 0.036) concentrations with serum TBIL level (Supplementary Table 4).
3.5.2 Effects of EDCs on serum DBIL level
Univariate logistic regression analysis of data showed an association of serum NP concentration (OR: 1.465 , 95% CI: 1.114-1.928, P = 0.006) with serum DBIL level (Supplementary Table 5).
3.6 Data of hepatic function tests
In 462 hepatic function assay reports, the AST level of school-age children was between 2-107 U/L, with an average of 17.926 U/L; the ALT level was about 4.1-69 U/L, with an average of 27.184 U/L; the ALT/AST ratio was in 0.29-7, with an average of 1.834; the TBIL level was around 1.2-112 μmol/L, with an average of 10.545 μmol/L; the DBIL level was between 0.2-10.8 μmol/L, with an average of 0.2 μmol/L; The IBIL value was between 0.4-36.3 μmol/L, with an average of 8.161 μmol/L (Supplementary Table 6).
3.7 Comparison of TBIL, DBIL and IBILlevels by gender, age and address
The values of TBIL, DBIL and IBIL in the serum of school-age children in Zunyi were different on the gender, and the concentrations of TBIL and IBIL were different on the address. There was no statistical difference in the results of hepatic function at the age (Figure 6).
3.8 Correlation between environmental risk factors and hepatic function
The results of hepatic function as the dependent variable and the risk factors on the questionnaire as the independent variables, the results of the multiple linear regression analysis were shown in Table 6. Cosmetics used during pregnancy were positively correlated with ALT (P = 0.050) and AST (P = 0.021). There was a positive correlation between the frequency of hair spray and perfume use for children and the AST (P = 0.022) (Supplementary Table 7).
3.9 Correlations of EDCs (NP, BPA and DMP) concentrations with hepatic function by gender, age, and address
When the concentration of serum NP, BPA and DMP in school-age children was quartered, there was a significant difference in the association trend between NP and AST by sex (P■2 = 0.031, P■4 < 0.001) (Figure 7A), and there was also a significant association between NP and ALT/AST in women (P■1 < 0.001,P■2 = 0.042, P■3=0.009) (Figure 7B). By address, the correlation between NP and AST was significantly different in Bozhou district (P▲1 = 0.02, P▲3 = 0.006) (Figure 7C). The correlation between DMP and AST was also different in Bozhou district (P▲2 = 0.003) (Figure 7D). The correlation between DMP and ALT/AST was also different in Bozhou district (P●2 = 0.049,P▲1 = 0.003) (Figure 7E). The correlation between BPA and DBIL was different in Huichuan district (P●1 = 0.006,P●2 = 0.008, P●3 = 0.007) (Figure 7F). There was no difference by age.