In vivo exposure to electronic waste (e-waste) leachate and hydraulic fracturing fluid adversely impacts the male reproductive system

Human health effects can arise from unregulated manual disassembly of electronic waste (e-waste) and/or hydraulic fracturing fluid spills. There is limited literature on the effects of e-waste and hydraulic fracturing wastewater exposure on the male reproductive system. Thus, this proof-of-concept study begins to address the question of how wastewater from two potentially hazardous environmental processes could affect sperm quality. Therefore, three groups of eight-week-old adult mice were exposed (5 d/wk for 6 wks) via a mealworm (Tenebrio molitor and Zophabas morio) feeding route to either: (1) e-waste leachate (50% dilution) from the Alaba Market (Lagos, Nigeria); (2) West Virginia hydraulic fracturing flowback (HFF) fluid (50% dilution); or, (3) deionized water (control). At 24-hours (hr), 3 weeks (wk), or 9-wk following the 6-wk exposure period, cohorts of mice were necropsied and adverse effects/persistence on the male reproductive system were examined. Ingestion of e-waste leachate or HFF fluid decreased number and concentration of sperm and increased both chromatin damage and numbers of morphological abnormalities in the sperm when compared to control mice. Levels of serum testosterone were reduced post-exposure (3- and 9-wk) in mice exposed to e-waste leachate and HFF when compared to time-matched controls, indicating the long-term persistence of adverse effects, well after the end of exposure. These data suggest that men living around or working in vicinity of either e-waste or hydraulic fracturing could face harmful effects to their reproductive health. From both a human health and economic standpoint, development of prevention and intervention strategies that are culturally relevant and economically sensitive are critically needed to reduce exposure to e-waste and HFF-associated toxic contaminants.

Exposure to cigarette smoke and Chlamydia pneumoniae infection in mice: Effect on infectious burden, systemic dissemination and cytokine responses: A pilot study

Cigarette smoke exposure has been considered a risk factor for infection with Chlamydia pneumoniae. C. pneumoniae infection is associated with respiratory tract infection and chronic respiratory disease, which is a serious public health concern. To determine whether prior exposure to cigarette smoke worsens C. pneumoniae infection (specifically, increases infectious burden and systemic dissemination) as well as alters cytokine responses in mice, adult female C57BL/6 mice were exposed to either filtered air (FA) or mainstream cigarette smoke (MCS) (15 mg/m(3), total suspended particulates) for 5 days/week for 2 weeks and then infected with C. pneumoniae (10(5) IFU) via intratracheal instillation. Mice were euthanized on Days 7, 14 or 26 post-infection (p.i.). Chlamydial burdens in the lungs and spleen were quantified by quantitative PCR (qPCR) and histologic analyses were performed; cytokine levels (TNFα, IL-4, IFNγ) in bronchoalveolar lavage fluid and serum were assayed by enzyme-linked immunosorbent assay (ELISA). The results indicated that: (1) mice exposed to either FA or MCS had similar chlamydial burdens in the lungs and spleen on Days 14 and 26 p.i.; (2) proximal and distal airway inflammation was observed on Day 14 p.i. in both FA and MCS mice, but persisted in MCS mice until Day 26 p.i.; FA exposed mice demonstrated resolution of distal airway inflammation; and (3) MCS mice displayed higher serum levels of IFNγ and IL-4 on Day 26 p.i. These findings indicate that exposure of mice to MCS (at a concentration equivalent to smoking < 1 pack cigarettes/day) led to greater C. pneumoniae-induced inflammation, as indicated by prolonged inflammatory changes.

Maternal allergy acts synergistically with cigarette smoke exposure during pregnancy to induce hepatic fibrosis in adult male offspring

Maternal environmental exposures during pregnancy are known to affect disease onset in adult offspring. For example, maternal asthma exacerbations during pregnancy can worsen adult asthma in the offspring. Cigarette smoking during pregnancy is associated with future onset of cardiovascular disease, obesity and diabetes. However, little is known about the effect of maternal environmental exposures on offspring susceptibility to liver disease. This pilot study examined the long-term effect of maternal allergen challenge and/or cigarette smoking during pregnancy on hepatic inflammation and fibrosis in adult mouse offspring. Ovalbumin (OVA) or phosphate-buffered saline (PBS)-sensitized/challenged CD-1 dams were exposed to mainstream cigarette smoke (MCS) or filtered air from gestational day 4 until parturition. Eight weeks postnatally, offspring were sacrificed for comparison of hepatic histology and mRNA expression. Adult male offspring of OVA-sensitized/challenged dams exposed to MCS (OSM) displayed significantly increased liver fibrosis (9.2% collagen content vs. <4% for all other treatment groups). These mice also had 1.8-fold greater collagen 1A1 mRNA levels. From the results here, we concluded that maternal allergen challenge in combination with cigarette smoke exposure during pregnancy may be an important risk factor for liver disease in adult male offspring.