Pesticide Residues in Man - Pesticides: Evaluation of Environmental Pollution - page 474

TABLE 15.1
Concentration (95th Percentile ng/g Serum) of Selected Organochlorine Pollutants in Serum
Samples from US Population (1999/2000) Based on Age, Gender, and Race or Ethnicity

Parameter β-HCH p,p ′ -DDE Oxychlordane HE a PCBs b

Age group
12-19 years

0.05 2.31 <LOD <LOD 2.87

20 years and older 0.48 12.33 0.33 0.19 3.04

Gender
Male

0.29 9.63 0.30 0.15 111.00 c

Female 0.56 13.20 0.32 0.20 118.00 c

Race or ethnicity
Mexican Americans

0.91 31.52 0.28 0.17 0.47 c

Non-Hispanic Black 0.36 14.56 0.31 0.11 1.27 c

Non-Hispanic
White

0.39 8.04 0.32 0.18 0.70 c

Source: Adapted from Needham, L. L., Barr, D. B., Caudill, S. P., et al. 2005. Concentrations of environmental
chemicals associated with neurodevelopmental effects in U.S. population. Neurotoxicology 26:
531-554.
a Heptachlor epoxide.
b The measured PCB congeners represent 11 compounds of numbers: 74, 99, 105, 118, 138, 146, 153, 156, 170,
180, 187.
c The values for PCB 153 only.

Concentration data of selected metals, persistent organic pollutants (POPs), organophospho-
rus (OP) and carbamate insecticides, and cotinine were presented. For example, the 95th
percentile estimates for serum total PCBs (whole weight) in the population aged 20 years
and older are about 2.7 ng/g, and for serum dioxin, the total toxic equivalence is between 40
and 50 pg/g lipid basis. The authors stated that the US general population is daily exposed
to many environmental chemicals, some of which are associated with neurodevelopmental
effects; however, human levels of these chemicals are decreasing over time in the US popula-
tion. This reflects the effects of legislation, industry efforts, and changes in lifestyle and activ-
ity patterns in the US population. Based on the authors' data, Table 15.1 summarizes serum
concentrations of β-HCH, p,p′-DDE, oxychlordane, heptachlor epoxide, and PCB congeners.
It clarifies that older and female subjects retain higher concentration levels of the measured
pollutants than younger and male subjects. Persons of different races or ethnicities differed
in their serum contaminant levels based on the measured compounds. For example, β-HCH
and p,p′-DDE levels were higher in the Mexican Americans than in the non-Hispanic (black
or white) persons; however, the non-Hispanic blacks showed the highest serum concentration
of PCB 153 (1.27 ng/g serum).
Serum samples from 83 farmers exposed to pesticides through their work in 14 different
fruit and vegetable farm stations, in addition to 5 normal control persons, living in a rural
area in Pakistan (Gadap, Karachi) were examined for the presence of pesticide residues
and enzyme levels in their blood (Azmi et al. 2006). The analysis indicated that there was a
significant difference in the residue levels in exposed and unexposed persons. Moreover,
there was a direct relation between the high residue levels and their enzyme levels (e.g.,
ALT, GOT, GPT, and ALP). The results shown in Table 15.2 indicate the prevalence of
cypermethrin and monocrotophos among the subjects in 13 farm stations. DDT and DDE,
diazinon, and deltamethrin were less frequently detected. Profenofos was detected at a