SciCombinator

Discover the most talked about and latest scientific content & concepts.

Journal: Environmental research

68

Personal care products are a source of exposure to endocrine disrupting and asthma-associated chemicals. Because use of hair products differs by race/ethnicity, these products may contribute to exposure and disease disparities.

32

Poor mental health in childhood has implications for health and wellbeing in later life. Natural space may benefit children’s social, emotional and behavioural development. We investigated whether neighbourhood natural space and private garden access were related to children’s developmental change over time. We asked whether relationships differed between boys and girls, or by household educational status.

Concepts: Psychology, Sociology, Child, Childhood, Adolescence, Developmental psychology, Child development, Universe

28

BACKGROUND: Several studies have linked biomass cooking fuel with adverse pregnancy outcomes such as preterm births, low birth weight and post-neonatal infant mortality, but very few have studied the associations with cooking fuel independent of other factors associated with stillbirths. METHOD: We analyzed the data from 188,917 ever-married women aged 15-49 included in India’s 2003-2004 District Level Household Survey-II to investigate the association between household use of cooking fuels (liquid petroleum gas/electricity, kerosene, biomass) and risk of stillbirth. Prevalence ratios (PRs) were obtained using Poisson regression with robust standard errors after controlling for several potentially confounding factors (socio-demographic and maternal health characteristics). RESULTS: Risk factors significantly associated with occurrence of stillbirth in the Poisson regression with robust standard errors model were: literacy status of the mother and father, lighting fuel and cooking fuel used, gravida status, history of previous abortion, whether the woman had an antenatal check up, age at last pregnancy >35 years, labor complications, bleeding complications, fetal and other complications, prematurity and home delivery. After controlling the effect of these factors, women who cook with firewood (PR 1.24; 95% CI: 1.08-1.41, p=0.003) or kerosene (PR 1.36; 95% CI: 1.10-1.67, p=0.004) were more likely to have experienced a stillbirth than those who cook with LPG/electricity. Kerosene lamp use was also associated with stillbirths compared to electric lighting (PR 1.15; 95% CI: 1.06-1.25, p=0.001). The population attributable risk of firewood as cooking fuel for stillbirths in India was 11% and 1% for kerosene cooking. CONCLUSION: Biomass and kerosene cooking fuels are associated with stillbirth occurrence in this population sample. Assuming these associations are causal, about 12% of stillbirths in India could be prevented by providing access to cleaner cooking fuel.

Concepts: Regression analysis, Pregnancy, Childbirth, Demography, Gasoline, Petroleum, Obstetrics, Abortion

28

Most studies examining the temperature-mortality association in a city used temperatures from one site or the average from a network of sites. This may cause measurement error as temperature varies across a city due to effects such as urban heat islands. We examined whether spatiotemporal models using spatially resolved temperatures produced different associations between temperature and mortality compared with time series models that used non-spatial temperatures. We obtained daily mortality data in 163 areas across Brisbane city, Australia from 2000 to 2004. We used ordinary kriging to interpolate spatial temperature variation across the city based on 19 monitoring sites. We used a spatiotemporal model to examine the impact of spatially resolved temperatures on mortality. Also, we used a time series model to examine non-spatial temperatures using a single site and the average temperature from three sites. We used squared Pearson scaled residuals to compare model fit. We found that kriged temperatures were consistent with observed temperatures. Spatiotemporal models using kriged temperature data yielded slightly better model fit than time series models using a single site or the average of three sites' data. Despite this better fit, spatiotemporal and time series models produced similar associations between temperature and mortality. In conclusion, time series models using non-spatial temperatures were equally good at estimating the city-wide association between temperature and mortality as spatiotemporal models.

Concepts: Regression analysis, Fundamental physics concepts, Temperature, Thermodynamics, Heat, Interpolation, Urban heat island, Kriging

27

Many common environmental chemicals are mammary gland carcinogens in animal studies, activate relevant hormonal pathways, or enhance mammary gland susceptibility to carcinogenesis. Breast cancer’s long latency and multifactorial etiology make evaluation of these chemicals in humans challenging.

Concepts: Cancer, Breast cancer, Organ, Mammal, Breast, Exocrine gland, Mammary gland, Mammary tumor

27

The relationship between environmental noise and health has been examined in depth. In view of the sheer number of persons exposed, attention should be focused on road traffic noise. The city of Madrid (Spain) is a densely populated metropolitan area in which 80% of all environmental noise exposure is attributed to traffic. The aim of this study was to quantify avoidable deaths resulting from reducing the impact of equivalent diurnal noise levels (LeqD) on daily cardiovascular and respiratory mortality among people aged ≥65 years in Madrid. A health impact assessment of (average 24h) LeqD and PM2.5 levels was conducted by using previously reported risk estimates of mortality rates for the period 2003-2005: For cardiovascular causes: LeqD 1.048 (1.005, 1.092) and PM2.5 1.041(1.020, 1.062) and for respiratory causes: LeqD 1.060 (1.000, 1.123) and PM2.5 1.030 (1.000, 1.062). The association found between LeqD exposure and mortality for both causes suggests an important health effect. A reduction of 1dB(A) in LeqD implies an avoidable annual mortality of 284 (31, 523) cardiovascular- and 184 (0, 190) respiratory-related deaths in the study population. The magnitude of the health impact is similar to reducing average PM2.5 levels by 10µg/m(3). Regardless of air pollution, exposure to traffic noise should be considered an important environmental factor having a significant impact on health.

Concepts: Epidemiology, Demography, Population, Population ecology, Population density, Pollution, Noise pollution, Air pollution

27

As part of the only national survey of lead in Australian children, which was undertaken in 1996, lead isotopic and lead concentration measurements were obtained from children from 24 dwellings whose blood lead levels were ≥15µg/dL in an attempt to determine the source(s) of their elevated blood lead. Comparisons were made with data for six children with lower blood lead levels (<10µg/dL).

Concepts: Concentration

27

We investigated the presence, levels, relationships, and risks of HCHs, DDTs, chlordanes, mirex, PCBs, and brominated flame retardants (BFRs) in terrestrial and aquatic bird eggs from an area in South Africa where DDT is used for malaria control. We found one of the highest ΣDDT levels reported this century; 13000ng/gwm (wet mass) in Grey Heron eggs which exceeds critical levels for reproductive success (3000ng/gwm) calculated for Brown Pelicans, with a no-effect level estimated at 500ng/gwm. Even higher ΣDDT levels at 16000ng/gwm were found in House Sparrow eggs (possibly the highest ever recorded for sparrows), with a maximum of 24400ng/gwm. Significant eggshell thinning in Cattle Egrets (33% between thickest and thinnest) was associated with increased levels of p,p'-DDT and p,p'-DDE. There were indications of unknown use of DDT and lindane. Relative to DDT, PCBs and BFRs levels were quite low. Ordinated data showed that different terrestrial pollutant profiles converged to a homogenised aquatic profile. Converging profiles, high levels of DDT in heron and sparrow eggs, and thinning eggs shells, indicate risk and impacts at release, in the aquatic environment, and in between. If characteristic life-strategies of birds in warm areas (e.g. longer-lived and fewer eggs per clutch) increases the risk compared with similar birds living in colder regions when both experience the same environmental pollutant levels, then malaria control using DDT probably has more significant impacts on biota than previously realised. Therefore, risk assessment and modelling without hard data may miss crucial impacts and risks, as the chemical use patterns and ecologies in Africa and elsewhere may differ from the conditions and assumptions of existing risk assessment and modelling parameters. Consideration of other findings associated with DDT from the same area (intersex in fish and urogental birth defects in baby boys), together with the findings of this study (high levels of DDT in bird eggs, eggshell thinning in the Cattle Egrets, and the apparent absence of breeding piscivore birds in the sprayed area) are strongly suggestive of negative impacts from DDT spraying for Malaria control. Our data presents strong arguments for an expedited process of replacing DDT with sustainable methods.

Concepts: Malaria, Risk, Bird, Risk management, House Sparrow, Sparrow, Heron, Cattle Egret

27

Few studies on natural estrogens have been conducted in agricultural ecosystems. High (up to 58ng/L) estrone concentrations were measured shortly after applications of manure in a small agricultural watershed. No other estrogens (17ß-estradiol, estrone or estriol) were detected afterward (first three rainfalls after applications). Results suggest that aquatic organisms in agricultural watersheds could be exposed to estrone shortly after manure applications, probably from leaching of land-applied animal wastes, but that this exposure would be short-lived.

Concepts: Agriculture, Estrogen, Ecosystem, Estrogens

27

BACKGROUND: Whether long-term, low-level hydrogen sulfide (H2S) gas is a cause of health effects, including asthma, is uncertain. Rotorua city, New Zealand, has the largest population exposed, from geothermal sources, to relatively high ambient levels of H2S. In a cross-sectional study, the authors investigated associations with asthma in this population. METHODS: A total of 1637 adults, aged 18-65 years, were enrolled during 2008-2010. Residences and workplaces were geocoded. H2S exposures at homes and workplaces were estimated using city-wide networks of passive H2S samplers and kriging to create exposure surfaces. Exposure metrics were based on (1) time-weighted exposures at home and work; and (2) the maximum exposure (home or work). Exposure estimates were entered as quartiles into regression models, with covariate data. RESULTS: Neither exposure metric showed evidence of increased asthma risk from H2S. However, some suggestion of exposure-related reduced risks for diagnosed asthma and asthma symptoms, particularly wheezing during the last 12 months, emerged. With the maximum exposure metric, the prevalence ratio for wheeze in the highest exposure quartile was 0.80 (0.65, 0.99) and, for current asthma treatment, 0.75 (0.52, 1.08). There was no evidence that this was caused by a “survivor effect”. CONCLUSIONS: The study provided no evidence that asthma risk increases with H2S exposure. Suggestions of a reduced risk in the higher exposure areas are consistent with recent evidence that H2S has signaling functions in the body, including induction of smooth muscle relaxation and reduction of inflammation. Study limitations, including possible confounding, preclude definitive conclusions.

Concepts: Regression analysis, Asthma, Risk, Smooth muscle, Hydrogen sulfide, Covariate, Natural gas, Wheeze