High prevalence of micropenis in 2710 male newborns from an intensive‐use pesticide area of Northeastern Brazil

Abstract

Exposure to endocrine-disrupting chemicals (EDCs) has been suggested to contribute to the increasing trends of external genital malformation in male newborns. In Northeastern Brazil, the poor sanitary conditions found in the favelas encourage the widespread use of pesticides. This 2-year study of a total birth cohort of full-term male newborns in the regional hospitals of Campina Grande (Paraíba, Brazil) sought to (1) accurately establish for the first time the incidences of neonatal male genital malformations, (2) investigate the endocrine and genetic aetiologies of these malformations, and (3) evaluate their associations with possible prenatal exposure to EDCs. A total of 2710 male newborns were explored for cryptorchidism, hypospadias and micropenis. Cases were referred to the Pediatric Endocrine Clinic for endocrine and genetic investigations, and all parents were interviewed about their environmental/occupational exposure to EDCs before/during pregnancy by paediatric endocrinologists using a detailed questionnaire. We observed 56 cases of genital malformation (2.07%), including 23 cryptorchidism (0.85%), 15 hypospadias (0.55%), and 18 micropenis (0.66%). All cases exhibited normal/subnormal testosterone production and none presented androgen receptor or 5α-reductase gene mutation. More than 92% of these newborns presented foetal contamination by EDCs, as their mothers reported daily domestic use of pesticides (i.e., DDT) and other EDCs. Most of these undervirilized male newborns presented additional EDC contamination, as 80.36% of the mothers and 58.63% of the fathers reported paid or unpaid work that entailed the use of pesticides and other EDCs before/during pregnancy for the mothers and around the time of fertilization for the fathers. The high rate of micropenis in our population associated with an elevated percentage of parental environmental/occupational exposure to EDCs before/during pregnancy indicates that foetal contamination may be a risk factor for the development of male external genital malformation.

Agrotóxicos e seus impactos na saúde humana e ambiental: uma revisão sistemática

“…Além de todos esses efeitos já apresentados, os agrotóxicos podem, também, estar relacionados a alterações no binômio mãe-feto, como malformações congêni-tas 108-111 , nascimentos prematuros, índices de apgar insatisfatórios 9,112 e micropênis em recém-nascidos 113 .…”

Estrogen-Induced Maldevelopment of the Penis Involves Down-Regulation of Myosin Heavy Chain 11 (MYH11) Expression, a Biomarker for Smooth Muscle Cell Differentiation1

“…Similarly, estrogen exposure has been linked with higher frequency of reproductive abnormalities [15]. A high prevalence of micropenis was reported in newborns from Brazil [16] and in infants and prepubescent boys from Denmark [17] whose mothers were exposed to pesticides during pregnancy. Laboratory animals treated prenatally with estrogens developed hypospadias [18,19].…”

Neurotoxicity of a Biopesticide Analog on Zebrafish Larvae at Nanomolar Concentrations

“…For instance, many studies showed that contaminations of rivers with estrogenic and androgenic compounds in the ng/L range, are responsible for intersex changes within fish populations [3,4] raising concerns about population-level consequences [5]. In Brazil, a study conducted in 2710 newborn males revealed fetal contamination with organochlorine pesticides (DDT) with a risk factor for external genital malformations [6], whereas in young girls, fetal and/or environmental exposure to endocrine disrupting chemicals (EDCs) led to precocious puberty [7,8]. …”