Faculty Bibliography

BACKGROUND:Cross-sectional studies have linked greater polychlorinated biphenyl (PCB) exposure to adverse neuropsychological effects in older adults, including learning, memory, and depressive symptoms. However, no studies among older adults have evaluated the association over time. OBJECTIVES:To assess the effect of serum PCB levels on neuropsychological function over a 14-year period in a cohort of older men and women from a PCB-contaminated area of New York State. METHODS:In 2000-2002, we assessed serum PCB levels and neuropsychological function (including the California Verbal Learning Test Trial 1 (CVLTT1) for verbal memory and learning, and the Beck Depression Index (BDI) for depressive symptoms) in 253 men and women, ages 55-74 years. A total of 116 (46%) persons repeated the PCB and neuropsychological assessment 14 years later. To assess the association over time, we used generalized estimating equations with clustering variables time, total PCB (∑PCB), and ∑PCB × time, and adjusted for baseline age, sex, smoking, and total serum-lipids. For statistically significant ∑PCB × time interactions, we evaluated the association between PCBs and either verbal memory and learning or depressive symptoms while holding ∑PCB constant at the 10th and 90th percentiles to clarify the direction of the interaction. RESULTS:Over the study period, serum ∑PCB levels (wet-weight) declined by 22%, and were associated with different patterns of change over time for memory (∑PCB × Time β = 0.08 p = 0.009) and depressive symptoms (∑PCB × Time β = -0.16 p = 0.013). Specifically, verbal memory and learning decreased (β = -0.08 p = 0.008) and depressive symptoms increased (β = 0.17 p = 0.008) among persons with low exposure (∑PCB levels at the 10th percentile), while persons with high exposure (90th percentile) showed non-significant improvements. DISCUSSION:In this cohort, declining ∑PCB levels were likely due at least in part to low rates of local fish consumption in recent decades, given the ban since 1976. The decreased verbal memory and learning and increased depressive symptoms over time among persons with low serum ∑PCB levels is consistent with studies of normative aging. However, the small improvements in those outcomes among those with high serum ∑PCB levels was unexpected. Healthy survivor selection bias or uncontrolled confounding may explain this result. It may also indicate that the neurotoxic impacts of PCBs in older adults are not permanent, but future studies are needed to confirm this possibility.

OBJECTIVE:To compare association of perfluoroalkyl substances (PFASs) with metabolic syndrome (MetS) profile among firefighters (FF) at airport to suburban FF. METHODS:Cross-sectional exploratory study, 47 men FF aged 18 to 62 years were enrolled from two fire departments in Ohio. Association between MetS outcome and log transformed serum concentrations of four PFASs was evaluated using multivariable logistic regression. RESULTS:PFASs serum concentrations were 18% to 74% higher in FF than the general population, and 21% to 62% higher in airport FF than suburban FF. Compared with US general population, an elevated risk of hypertension was noted in FF, but no significant association between PFASs and MetS was found. CONCLUSIONS:Current serum PFASs in FF are not associated with MetS risk.

Similar to humans, pet animals are exposed to environmental contaminants through multiple sources and pathways. Although a few studies have demonstrated exposure of cats and dogs to environmental chemicals, little is known about exposure to bisphenols, benzophenone UV filters, and antibacterial agents. In this study, we measured three bisphenols, three benzophenone-type UV filters, triclosan (TCS), and triclocarban (TCC) in dog (n = 50) and cat urine (n = 50) collected from New York State, USA. Among bisphenols, BPS was found at the highest concentrations (mean ± SD: 3.2 ± 8.5 ng/mL in dogs and 8.85 ± 30.0 ng/mL in cats) with detection frequencies of 96% in dogs and 78% in cats. Among benzophenones, BP-3 (oxybenzone) was the dominant compound in pet urine, followed by BP-1 and BP-8. TCS was found at concentrations higher than those of TCC in both cat and dog urine. There were no significant differences in bisphenol concentrations between sexes or age groups, both in dogs and cats. The calculated hazard quotients (HQ) suggested that the current exposure levels of BPS and BP-3 in pets were 2-5 orders of magnitude below the tentative threshold values available for humans.

Exposure to diethylhexyl phthalate (DEHP), the most abundant plasticizer used in the production of polyvinyl-containing plastics, has been associated to adverse reproductive health outcomes in both males and females. While the effects of DEHP on reproductive health have been widely investigated, the molecular mechanisms by which exposure to environmentally-relevant levels of DEHP and its metabolites impact the female germline in the context of a multicellular organism have remained elusive. Using the Caenorhabditis elegans germline as a model for studying reprotoxicity, we show that exposure to environmentally-relevant levels of DEHP and its metabolites results in increased meiotic double-strand breaks (DSBs), altered DSB repair progression, activation of p53/CEP-1-dependent germ cell apoptosis, defects in chromosome remodeling at late prophase I, aberrant chromosome morphology in diakinesis oocytes, increased chromosome non-disjunction and defects during early embryogenesis. Exposure to DEHP results in a subset of nuclei held in a DSB permissive state in mid to late pachytene that exhibit defects in crossover (CO) designation/formation. In addition, these nuclei show reduced Polo-like kinase-1/2 (PLK-1/2)-dependent phosphorylation of SYP-4, a synaptonemal complex (SC) protein. Moreover, DEHP exposure leads to germline-specific change in the expression of prmt-5, which encodes for an arginine methyltransferase, and both increased SC length and altered CO designation levels on the X chromosome. Taken together, our data suggest a model by which impairment of a PLK-1/2-dependent negative feedback loop set in place to shut down meiotic DSBs, together with alterations in chromosome structure, contribute to the formation of an excess number of DSBs and altered CO designation levels, leading to genomic instability.

Approximately 200 million m³ of sediments are dredged every year in the United States. Of this amount, 2.3-9 million m³ are contaminated to the extent that they require special, and often costly, handling. Therefore, there is a pressing need to develop appropriate technology for the safe utilization of these sediments, especially in the case of the Hudson River, which is well known to demonstrate significant polychlorinated biphenyls (PCBs) contamination. Hence, the aim of the present study was to examine the influence of different doses of Hudson River sediments (10%, 25%, 50%, 75% and 100% admixtures) on soil quality and on the biochemical and growth response of cucumber (Cucumis sativus L. cv 'Wisconsin SMR 58'), used as potential phytoremediation tool for sediment-borne PCBs. A sediment/soil admixture was found to significantly decrease the nitrogen (N) content in the substratum; in addition, phosphorus (P) content was significantly increased by 50-100% sediment, while potassium (K) content was significantly increased by 10% sediment, and significantly decreased by >50% sediment. Although sediment treatment resulted in a gradual increase in PCB content in the soil-sediment substratum, exceeding the threshold effect concentration (TEC) for the ≥50% sediment admixture, the Microtox assay did not suggest toxicity to microorganisms. The results demonstrated also that admixture of 10-25% Hudson River sediment increased cucumber growth; however, higher doses led to growth inhibition, manifested as lower biomass and smaller leaves. Also, chlorophyll a and b content decreased with increasing doses of sediment. Phenylpropanoid and flavonol contents were significantly higher in plants grown in soil amended with 10% of sediment, but significantly lower in soil treated with a 100% sediment admixture. The anthocyanin content in plants was lower at admixtures of 50% and higher. The obtained results corresponded with the decreasing content of N and K.

We derive differential equations to determine the kinetics of gas/particle partitioning of semi-volatile organic compounds (SVOCs). These equations model the transient states from initiation of sorption to particles (non-steady state) through the establishment of steady state. Two hypothetical scenarios are examined: (1) exchange of SVOCs between gas- and particle-phases alone; and (2) both gas/particle partitioning and wet and dry deposition of particles. The differential equations show that, under Scenario 1, a steady state is reached as an equilibrium between gas- and particle-phases, whereas under Scenario 2, the attained steady state is not in equilibrium. Our model shows that SVOCs in atmosphere where particle deposition is occurring reach a steady non-equilibrium state sooner than they would reach equilibrium under Scenario 1. We infer that SVOCs in the atmosphere will reach steady state instead of equilibrium between gaseous and particulate phases in circumstances where wet and dry deposition of particles cannot be neglected. In addition, our study indicates that the time for SVOCs to reach steady state in the atmosphere is fast, most likely within minutes or hours, suggesting that SVOCs are in steady or quasi-steady state in the atmosphere. Our analysis also reveals that gas/particle partitioning and particle deposition of SVOCs are dependent on each other.

Melamine-based resins are used extensively in fabrics to impart fire and heat resistance as well as wrinkle-free properties. Little is known, however, regarding the occurrence of melamine and its derivatives in textiles. In this study, concentrations of melamine, ammeline, ammelide, and cyanuric acid were determined in 77 textile samples and infant clothing purchased from Albany, New York, USA. All textile samples contained one or more target analytes, at concentration ranges of 1.19-81,800, 3.21-17,800, <1.20-25,700, and <0.50-550 ng/g for melamine, cyanuric acid, ammeline, and ammelide, respectively. Melamine was the predominant compound, accounting for 52% of the total concentrations of four analytes (i.e., ∑melamines). Significant positive correlations were found between the concentrations of melamine and its three derivatives (0.347 < r < 0.862, p < .01). The concentrations of ∑melamines were significantly higher in cotton fabrics (mean: 10,500 ng/g) and cotton clothes (10,200 ng/g) than in synthetic fabrics (1,380 ng/g) and socks (40.0 ng/g) (p < .01). Simulated laundry experiments suggested that a single round of washing with water removed 76-90% of melamine from clothing. The calculated dermal exposure doses of melamine and cyanuric acid were three to four orders of magnitude below the reference value. This study provides the first evidence of the occurrence of melamine derivatives in textiles and clothing purchased in the United States. CAPSULE: Melamine and cyanuric acid are widely distributed in textiles and infant clothing collected from the United States.