Pesticide Residues in Man - Pesticides: Evaluation of Environmental Pollution - page 479

Ninety-two Egyptian school children (46 girls and 46 boys), living in urban Giza,
were studied for chronic exposure to OCP residues (Sherif et al. 2005). Varying levels
of OCP residues were detected in the urine samples of 36 of the 92 studied children;
constituting 39% of the total. The most frequently detected residues were p,p′-DDE
(36.1%) and p,p′-DDT (22.2%). α-HCH and heptachlor epoxide were not detected in the
urine samples.
Panuwet et al. (2009) evaluated the exposure to pesticides among secondary school stu-
dents aged 12-13 years old in Chiang Mai Province, Thailand. A total of 207 urine samples
were analyzed for 18 specific pesticide metabolites. The authors found 14 metabolites
in the urine samples tested; 7 of them were detected with a frequency >17%. The most
frequently detected metabolites were 2-[(dimethoxyphosphorothioyl)sulfanyl] succinic
acid (MDA), PNP, TPCY (metabolite of chlorpyrifos), 2,4-dichlorophenoxyaceticacid
(2,4-D), cis- and trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylicacids
(c - DCCA and t-DCCA; metabolite of permethrin), and 3-phenoxybenzoicacid (3-PBA;
metabolite of pyrethroids). The students were classified into four groups according to
their parental occupations: farmers (N = 60), merchants and traders (N = 39), govern-
ment and company employees (N = 52), and laborers (N = 56). Children of the farmers
had significantly higher urinary concentrations of pyrethroid insecticide metabolites
than did other children (p < 0.05). Similarly, children of the agricultural families had
significantly higher pyrethroid metabolite concentrations (Figure 15.5). Males had
significantly higher values of PNP; however, no other sex-related differences were
observed. Because parental occupation and agricultural activities seemed to have little

4.5

Farmers (N = 60)
Merchants & traders
(N = 39)
Government &
company employees
(N = 52)
Laborers (N = 56)

4

3.5

3

2.5

2

1.5

1

0.5

0

MDA PNP 2,4-D TCPY trans-

DCCA

cis-
DCCA

3-PBA

Metabolites

FIGURE 15.5
Major specific pesticide metabolites detected in urine samples of school students from northern Thailand as
classified by parental occupation. Metabolite abbreviation corresponding to the parental pesticide : MDA, Malathion;
PNP, Parathion; 2,4-D, 2,4-Dichlorophenol; TCPY, Chlorpyrifos; cis-DCCA and trans-DCCA, Cyfluthrin,
Permethrin, Cypermethrin; 3-PBA, Most of the commercially available pyrethroids. (Adapted from Panuwet, P.,
Prapamontol, T., Chantara, S., and Barr, D. B. 2009. Urinary pesticide metabolites in school students from
northern Thailand. Int. J. Hyg. Environ. Health 212: 288-297.)