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Perfluoroalkyl substances exposure and risk of polycystic ovarian syndrome related infertility in Chinese women
2019
Wang, Wei | Zhou, Wei | Wu, Ziyuan | Liang, Fan | Li, Yan | Zhang, Jun | Cui, Linlin | Feng, Yan | Wang, Yan
Perfluoroalkyl substances (PFASs) are a family of synthetic, fluorinated organic compounds. They have been widely used in industrial applications and consumer products and widespread in the environment, wildlife and human. Experimental and epidemiologic evidence suggested that PFASs are capable of interfering with endocrine processes and have potential reproductive and developmental toxicities. Polycystic ovarian syndrome (PCOS), one of the main reasons of female infertility, is a common endocrine disorder in reproductive age women. We performed a case-control study to evaluate associations between PCOS-related infertility and PFASs concentrations in plasma. A total of 180 infertile PCOS-cases and 187 healthy controls were recruited from the Center for Reproductive Medicine of Shandong University. Blood specimens were collected at enrollment and analyzed for ten PFASs using liquid chromatography-tandem mass spectrometry. Multivariable logistic regression procedure was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for each PFAS. Perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) were the dominant PFASs in the plasma of participants, with the median concentration of 5.07 ng/mL and 4.05 ng/mL, respectively. The median levels of individual PFAS were not significantly different between PCOS-cases and controls. While adjusted for the potential confounders (age, BMI, household income, education level, employment status, age at menarche, menstrual volume), the plasma concentration of perfluorododecanoic acid (PFDoA), a 12 carbons lengths of perfluorocarboxylic acids, was associated with a significantly increased risk of PCOS-related infertility (medium vs low tertile: OR = 2.36, 95% CI: 1.12, 4.99, P = 0.02; high vs low tertile: OR = 3.04, 95% CI: 1.19, 7.67, P = 0.02), with the P trend 0.01. No significant relationship was observed between PCOS-related infertility and other PFAS analytes in the adjusted model, despite perfluoroundecanoic acid showed a negative association (P trend 0.03). The potential reproductive health effects of PFASs and the underlying mechanisms merit further investigation in the future.
Mostrar más [+] Menos [-]The influence of lifestyle on airborne particle surface area doses received by different Western populations
2018
Pacitto, A. | Stabile, L. | Moreno, T. | Kumar, P. | Wierzbicka, A. | Morawska, L. | Buonanno, G.
In the present study, the daily dose in terms of particle surface area received by citizens living in five cities in Western countries, characterized by different lifestyle, culture, climate and built-up environment, was evaluated and compared. For this purpose, the exposure to sub-micron particle concentration levels of the population living in Barcelona (Spain), Cassino (Italy), Guilford (United Kingdom), Lund (Sweden), and Brisbane (Australia) was measured through a direct exposure assessment approach. In particular, measurements of the exposure at a personal scale were performed by volunteers (15 per each population) that used a personal particle counter for different days in order to obtain exposure data in microenvironments/activities they resided/performed. Non-smoking volunteers performing non-industrial jobs were considered in the study.Particle concentration data allowed obtaining the exposure of the population living in each city. Such data were combined in a Monte Carlo method with the time activity pattern data characteristics of each population and inhalation rate to obtain the most probable daily dose in term of particle surface area as a function of the population gender, age, and nationality.The highest daily dose was estimated for citizens living in Cassino and Guilford (>1000 mm²), whereas the lowest value was recognized for Lund citizens (around 100 mm²). Indoor air quality, and in particular cooking and eating activities, was recognized as the main influencing factor in terms of exposure (and thus dose) of the population: then confirming that lifestyle (e.g. time spent in cooking activities) strongly affect the daily dose of the population. On the contrary, a minor or negligible contribution of the outdoor microenvironments was documented.
Mostrar más [+] Menos [-]Can the integration of multiple biomarkers and sediment geochemistry aid solving the complexity of sediment risk assessment? A case study with a benthic fish
2012
Costa, Pedro M. | Caeiro, Sandra | Vale, Carlos | DelValls, T Àngel | Costa, Maria H.
Surveying toxicity of complex geochemical media as aquatic sediments often yields results that are either difficult to interpret or even contradictory to acknowledged theory. Multi-level biomarkers were investigated in a benthic fish exposed to estuarine sediments through laboratory and in situ bioassays, to evaluate their employment either in ecological risk assessment or in more mechanistic approaches to assess sediment-bound toxicity. Biomarkers reflecting lesions (such as genotoxicity or histopathology), regardless of their low or absent specificity to contaminants, are efficient in segregating exposure to contaminated from uncontaminated sediments even when classical biomarkers like CYP1A and metallothionein induction are inconclusive. Conversely, proteomics and gene transcription analyses provided information on the mechanics of toxicity and aided explaining response variation as a function of metabolic imbalance and impairment of defences against insult. In situ bioassays, although less expedite and more affected by confounding factors, produced data better correlated to overall sediment contamination.
Mostrar más [+] Menos [-]Factory employment exposure and human health: Evidence from rural China
2020
Xu, Xiangbo | Sun, Mingxing | Zhang, Linxiu | Fu, Chao | Bai, Yunli | Li, Chang
Quantitating the health effects of employment history in factories, especially polluting ones, is essential for understanding the benefits or losses of industrialization in rural areas. Using a traced subset of nationwide panel data from 2005 covering five provinces, 101 villages, and 2026 households (collected recently in 2016) and the econometric models, this study estimated the effect of factory employment history on workers' health. The results showed that: the absolute number of factory workers increased from 1998 to 2015, and the proportion of factory workers was 7.68% in 2015; the absolute number and the proportion of farmers decreased from 63.84% in 1998 to 29.06% in 2015. Given that all the respondents live in rural areas, the HlthPlace (the first place the individual went to for their last illness in 2015) was selected as the main dependent variable of interest, and Hlthexp (Healthcare expenditure per person at last illness in 2015) and self-reported health were used as auxiliary dependent variables. The findings revealed that, after controlling the characteristics of individual, household, hospital and area, a one year increase of factory employment history corresponded to a 0.035 level increase in the probability of people choosing high-level hospital (p < 0.01) and a 237.61 yuan increase in healthcare expenditure (p < 0.1). The results also showed the adverse effect of self-reported health on factory employment history (p < 0.01). In addition, the relationship between the farming history and health was evaluated, and the econometric results showed that compared with factory employment history, farming history had opposite impacts on health (p < 0.01). Finally, the robustness check showed that the empirical results were reliable and that the initial results were robust. Generally, this study revealed the effect of overall factory employment on health, which is a useful research supplement to the studies on the health effects of specific pollution exposure.
Mostrar más [+] Menos [-]Influence of socio-demographic and diet determinants on the levels of mercury in preschool children from a Mediterranean island
2013
Garí, Mercè | Grimalt, Joan O. | Torrent, Maties | Sunyer, Jordi
Mercury levels measured in 302 hair samples of 4 year-old children from Menorca (western Mediterranean Sea) are reported. Their concentrations, arithmetic mean 1.4 μg/g, ranging between 0.040 μg/g and 10 μg/g, were higher than in other children inland populations but lower than in previously studied island cohorts, e.g. Faroe, Madeira and Seychelles. 20% of the samples were above the WHO recommended values. Higher concentrations in females than males were observed. Frequent consumption of fish and other seafood were significantly related to the observed mercury concentrations. Oily fish was the main source of this pollutant but shellfish and squid consumption were also associated with high mercury concentrations. Maternal smoking, occupational status or previous siblings were also found to significantly influence the levels of this pollutant. McCarthy Scales of Children's Abilities used to assess children's motor and cognitive abilities did not show association with mercury concentrations at 4 years of age.
Mostrar más [+] Menos [-]Occupational exposure to volatile organic compounds and health risks in Colorado nail salons
2019
Lamplugh, Aaron | Harries, Megan | Xiang, Feng | Trinh, Janice | Hecobian, Arsineh | Montoya, Lupita D.
Nail salon technicians face chronic exposure to volatile organic compounds (VOCs), which can lead to adverse health outcomes including cancer. In this study, indoor levels of formaldehyde, as well as benzene, toluene, ethylbenzene and xylene, were measured in 6 Colorado nail salons. Personal exposure VOC measurements and health questionnaires (n = 20) were also performed; questionnaires included employee demographics, health symptoms experienced, and protective equipment used. Cancer slope factors from the United States Environmental Protection Agency (US EPA) and anthropometric data from the Centers for Disease Control and Prevention were then used to estimate cancer risk for workers, assuming 20-yr exposures to concentrations of benzene and formaldehyde reported here. Results show that 70% of surveyed workers experienced at least one health issue related to their employment, with many reporting multiple related symptoms. Indoor concentrations of formaldehyde ranged from 5.32 to 20.6 μg m−3, across all 6 salons. Indoor concentrations of toluene ranged from 26.7 to 816 μg m−3, followed by benzene (3.13–51.8 μg m−3), xylenes (5.16–34.6 μg m−3), and ethylbenzene (1.65–9.52 μg m−3). Formaldehyde levels measured in one salon exceeded the Recommended Exposure Limit from the National Institute for Occupational Safety and Health. Cancer risk estimates from formaldehyde exposure exceeded the US EPA de minimis risk level (1 × 10−6) for squamous cell carcinoma, nasopharyngeal cancer, Hodgkin's lymphoma, and leukemia; leukemia risk exceeded 1 × 10−4 in one salon. The average leukemia risk from benzene exposure also exceeded the US EPA de minimis risk level for all demographic categories modeled. In general, concentrations of aromatic compounds measured here were comparable to those measured in studies of oil refinery and auto garage workers. Cancer risk models determined that 20-yr exposure to formaldehyde and benzene concentrations measured in this study will significantly increase worker's risk of developing cancer in their lifetime.
Mostrar más [+] Menos [-]Knowledge gaps in ecotoxicology studies of marine environments in Pacific Island Countries and Territories – A systematic review
2020
Varea, Rufino | Piovano, Susanna | Ferreira, Marta
The Pacific Island Countries and Territories (PICTs) are heavily dependent on the marine resources for food security, employment, government revenue and economic development, hence the concern about the potential exposure of these resources to pollutants. The main goal of this review was to identify ecotoxicology studies published that were done in PICTs. Four major gaps were identified: i) a quantitative gap, with low number of studies published on the PICTs; ii) a geographic gap, where ecotoxicology studies have unevenly covered the different PICTs; iii) a temporal gap, as no biological effect monitoring study has so far been published for the PICTs; and, iv) a pollutants gap, as all of the PICTs studies focused mainly on environmental monitoring studying on average two types of pollutants (heavy metals and pesticides) per PICT only. We suggest, therefore, the potential risk to the marine environment to be estimated by assessing the fate of pollutants via chemical and biological effect monitoring.
Mostrar más [+] Menos [-]Pollution engineering practice handbook
1975
Cheremisinoff, Paul N. | Young, Richard A. (Richard Alan)
Has green finance facilitated China’s low-carbon economic transition?
2022
Li, Wenqi | Fan, Jingjing | Zhao, Jiawei
The transformation of the traditional high-carbon economy to a low-carbon economy and the change in the economic development mode urgently require the transformation and development of traditional finance to green finance. This study examines the impact of green finance on the transition to a low-carbon economy in 30 Chinese provinces from 2001 to 2019 and further explores the role of low-carbon technological innovation in this facilitation process. We use the Global Malmquist- Luenberger index to measure low-carbon total factor productivity using gross regional product as the desired output, CO2 emissions as the undesired output, and capital stock, employment, and total energy consumption as input indicators to represent the low-carbon economic transition. We select seven indicators in four dimensions of green credit, green securities, green insurance, and green investment to construct a comprehensive green finance evaluation system, and then apply the entropy value method to calculate green finance indicators. The number of patents granted for low-carbon innovation is used to measure low-carbon technology innovation. Foreign direct investment, industrialization level, economic development level, and urbanization level are selected as control variables. Through panel data model, mediating effect model and 2SLS, we find that green finance can significantly contribute to the transformation of low-carbon economy, but this contribution decreases with the intervention of low-carbon technology innovation. The implications of our empirical results can help China to improve the development of green finance and thus promote the transformation and upgrading of a low-carbon economy.
Mostrar más [+] Menos [-]Global warming and export competitiveness of agriculture sector: evidence from heterogeneous econometric analysis of Pakistan
2022
The increase in average annual temperature due to greenhouse gases emission is posing threat to the agriculture sector across the globe. Pakistan is labor abundant agrarian country that heavily depends on the agriculture sector for food, employment, and raw material for industries. This study is a preliminary investigation that explores the effect of increasing average annual temperature on the competitiveness of 24 major agricultural exports from 2003 to 2020. The revealed export advantage (RXA) is used to explore the competitive performance of selected agricultural exports, which is then normalized to examine the effect of increasing average annual temperature along with official exchange rate, urbanization, and globalization. The panel fixed-effect model with heteroscedasticity consistent robust standard error recommended by White (Econometrica 48(4):817–838, 1980) is used to explore model estimates, whereas the robustness check has been performed by using heteroscedasticity and multicollinearity consistent robust standard error model of Driscoll and Kaary (Rev Econ Stat 80(4):549–559, 1998). The estimated result reveals that the increasing average annual temperature has a negative but insignificant impact on the export competitiveness of selected agricultural exports. While, urbanization and exchange rate deprecation show a significant negative effect of higher intensity, respectively. Globalization, however, reveals a significant positive impact on the competitiveness of selected agricultural exports. This study, therefore, urges for the development of the agriculture sector by adopting SDGs proposed by the United Nations for sustainable economic growth and development.
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