Association between urinary biomarkers of exposure to organophosphate insecticides and serum reproductive hormones in men from NHANES 1999–2002

Abstract

Exposure to organophosphate (OP) insecticides may alter reproductive hormone levels in men and increase the risk for poor reductive health and other adverse health outcomes. However, relevant epidemiology studies in men are limited. We evaluated urinary concentrations of OP metabolites (3,5,6-trichloro-2-pyridinol and six dialkyl phosphates) in relation to serum concentrations of testosterone (T) and estradiol among 356 men aged 20–55 years old from the U.S. National Health and Nutrition Examination Survey. Biomarkers were detected in greater than 50% of the samples, except for diethyldithiophosphate, dimethylphosphate, and dimethyldithiophosphate. In adjusted regression models, we observed a statistically significant inverse relationship between diethyl phosphate (DEP) and T when DEP was modeled as either a continuous or categorical variable. These findings add to the limited evidence that exposure to certain OP insecticides is linked to altered T in men, which may have important implications for male health.

Environmental non-persistent endocrine-disrupting chemicals exposure and reproductive hormones levels in adult men

“…Meeker et al (2006Meeker et al ( , 2007 [38,39] revealed the negative association between urinary metabolites of insecticides and testosterone, estradiol and free androgen index. Omoike et al (2015) [40] showed such associations only with testosterone. In contrast Melgarejo et al (2015) [37] revealed the positive association between urinary concentrations of organophosphate pesticide metabolites and LH and FSH.…”

“…Due to extensive use of such pesticides, a large proportion of the population is exposed to these chemicals or their environmental degradation products. Four original papers referring to exposure to organophosphate pesticides and levels of reproductive hormones were included in the review [37][38][39][40]. Three of the studies were conducted in the USA [38][39][40] and one in Spain [37].…”

“…All of the studies were cross-sectional. Participants were male partners in couples presenting to an infertility clinics, except for Omoike et al (2015) [40] who derived data (subset of men (N = 356)) from the crosssectional US National Health and Nutrition Examination Survey (NHANES).…”

“…Phthalates were measured in urine [18][19][20][21][22]25,26], semen [23,27] and serum [24]. Parabens, synthetic pyrethroids and organophosphate pesticides were measured in urine samples [30,[33][34][35][36][37][38][39][40]. In most of the studies only one urine or various biological fluid samples were used for the exposure assessment purposes.…”

“…Smoking status was included as a potential risk factor in all the studies. Only in 3 studies [21,31,40] the smoking status was controlled by measuring the level of nicotine. The time of the day of blood/urine sample collection was adjusted in nearly a half of the studies [12,13,15,18,19,25,26,30,33,37,39], too.…”