Environmental Chemicals and Autism

A Scoping Review of the Human and Animal Research, 2019

The Endocrine Disruption Exchange newest scoping review finds that 152 environmental chemicals have been investigated in humans or animals for their association with autism. TEDX highlight the need for systematic review of lead, PCBs, and chlorpyrifos.

Abstract

Background
Estimates of autism prevalence have increased dramatically over the past two decades. Evidence suggests environmental factors may contribute to the etiology of the disorder.

Objectives
This scoping review aimed to identify and categorize primary research and reviews on the association between prenatal and early postnatal exposure to environmental chemicals and the development of autism in epidemiological studies and rodent models of autism.

Methods
PubMed was searched through 8 February 2018. Included studies assessed exposure to environmental chemicals prior to 2 months of age in humans or 14 d in rodents. Rodent studies were considered relevant if they included at least one measurement of reciprocal social communicative behavior or repetitive and stereotyped behavior. Study details are presented in interactive displays using Tableau Public.

Results
The search returned 21,603 unique studies, of which 54 epidemiological studies, 46 experimental rodent studies, and 50 reviews were deemed relevant, covering 152 chemical exposures. The most frequently studied exposures in humans were particulate matter (n=14), mercury (n=14), nonspecific air pollution (n=10), and lead (n=10). In rodent studies, the most frequently studied exposures were chlorpyrifos (n=9), mercury (n=6), and lead (n=4).

Discussion
Although research is growing rapidly, wide variability exists in study design and conduct, exposures investigated, and outcomes assessed. Conclusions focus on recommendations to guide development of best practices in epidemiology and toxicology, including greater harmonization across these fields of research to more quickly and efficiently identify chemicals of concern. In particular, we recommend chlorpyrifos, lead, and polychlorinated biphenyls (PCBs) be systematically reviewed in order to assess their relationship with the development of autism. There is a pressing need to move forward quickly and efficiently to understand environmental influences on autism in order to answer current regulatory questions and inform treatment and prevention efforts.

60 MiNueTs Toxic

UCSF Program on Reproductive Health and the Environment, 2017

Video published on 18 Apr 2019 by the UCSF Program on Reproductive Health and the Environment.

The University of California San Francisco (UCSF) Program on Reproductive Health and the Environment (PRHE)’s mission is to create a healthier environment for human reproduction and development through advancing scientific inquiry, clinical care and health policies that prevent exposures to harmful chemicals in our environment.

More Information

Adult and Prenatal Chemical Exposures

Breast Cancer Prevention Partners, with Tracey Woodruff, Ph.D., Mar 2019

  • How am I exposed to chemicals?
  • What are prenatal exposures?
  • How can I reduce my own personal exposures?
  • What more can I do to help make a change?

Featuring BCPP Science Advisory Panel member Tracey Woodruff, Ph.D., Director of the Program on Reproductive Health and the Environment, University of California, San Francisco, Professor in the Department of Obstetrics, Gynecology, and Reproductive Sciences and Philip R. Lee Institute for Health Policy Studies at UCSF

Why are ObGyns Talking Toxins ?

Let’s make environmental health part of health care

Doctors from 125 countries want policies to prevent exposure to toxic chemicals

Produced for PRHE by Susan Lamontagne, Public Interest Media Group, for the International Federation of Gynecology and Obstetrics (FIGO) XXI World Congress on September 30, 2015.

Why are Doctors Talking Toxins ?

And how to reduce exposure to toxic chemicals worldwide ?

It’s time to shift the burden of proof, from scientists, back to the chemical industry

Video published on 5 June 2019, by UCSF Program on Reproductive Health and the Environment.

Air pollution associated to psychotic experiences in young people

Association of Air Pollution Exposure With Psychotic Experiences During Adolescence

A new study finds that teens living in dirty air 70% more likely to have symptoms such as paranoia, the guardian reports. Image Duke University.

2019 Study Key Points

Question
Is exposure to air pollution associated with adolescent psychotic experiences?

Findings
In this nationally representative cohort study of 2232 UK-born children, significant associations were found between outdoor exposure to nitrogen dioxide, nitrogen oxides, and particulate matter and reports of psychotic experiences during adolescence. Moreover, nitrogen dioxide and nitrogen oxides together explained 60% of the association between urban residency and adolescent psychotic experiences.

Meaning
The association between urban residency and adolescent psychotic experiences is partly explained by the higher levels of outdoor air pollution in urban settings.

Abstract

Importance
Urbanicity is a well-established risk factor for clinical (eg, schizophrenia) and subclinical (eg, hearing voices and paranoia) expressions of psychosis. To our knowledge, no studies have examined the association of air pollution with adolescent psychotic experiences, despite air pollution being a major environmental problem in cities.

Objectives
To examine the association between exposure to air pollution and adolescent psychotic experiences and test whether exposure mediates the association between urban residency and adolescent psychotic experiences.

Design, Setting, and Participants
The Environmental-Risk Longitudinal Twin Study is a population-based cohort study of 2232 children born during the period from January 1, 1994, through December 4, 1995, in England and Wales and followed up from birth through 18 years of age. The cohort represents the geographic and socioeconomic composition of UK households. Of the original cohort, 2066 (92.6%) participated in assessments at 18 years of age, of whom 2063 (99.9%) provided data on psychotic experiences. Generation of the pollution data was completed on October 4, 2017, and data were analyzed from May 4 to November 21, 2018.

Exposures
High-resolution annualized estimates of exposure to 4 air pollutants—nitrogen dioxide (NO2), nitrogen oxides (NOx), and particulate matter with aerodynamic diameters of less than 2.5 (PM2.5) and less than 10 μm (PM10)—were modeled for 2012 and linked to the home addresses of the sample plus 2 commonly visited locations when the participants were 18 years old.

Main Outcomes and Measures
At 18 years of age, participants were privately interviewed regarding adolescent psychotic experiences. Urbanicity was estimated using 2011 census data.

Results
Among the 2063 participants who provided data on psychotic experiences, sex was evenly distributed (52.5% female). Six hundred twenty-three participants (30.2%) had at least 1 psychotic experience from 12 to 18 years of age. Psychotic experiences were significantly more common among adolescents with the highest (top quartile) level of annual exposure to NO2 (odds ratio [OR], 1.71; 95% CI, 1.28-2.28), NOx (OR, 1.72; 95% CI, 1.30-2.29), and PM2.5 (OR, 1.45; 95% CI, 1.11-1.90). Together NO2 and NOx statistically explained 60% of the association between urbanicity and adolescent psychotic experiences. No evidence of confounding by family socioeconomic status, family psychiatric history, maternal psychosis, childhood psychotic symptoms, adolescent smoking and substance dependence, or neighborhood socioeconomic status, crime, and social conditions occurred.

Conclusions and Relevance
In this study, air pollution exposure—particularly NO2 and NOx—was associated with increased odds of adolescent psychotic experiences, which partly explained the association between urban residency and adolescent psychotic experiences. Biological (eg, neuroinflammation) and psychosocial (eg, stress) mechanisms are plausible.

Stopping human-caused air pollution would prevent 5.6 million premature deaths per year

Effects of fossil fuel and total anthropogenic emission removal on public health and climate

If humans stopped emitting air, an astonishing 5.6 million premature deaths per year due to global outdoor air pollution could be prevented, according to research published Monday.

About 65% of these deaths are due to burning of fossil fuels, with the remainder due to such activities as biomass burning and agriculture. Eliminating human-caused air pollution would also significantly reduce drought in monsoon regions, but it would allow more sunlight to reach the surface, increasing Earth’s surface temperature by at least 0.36°C (0.65°F). Overall, the effects would be hugely beneficial, Wunderground reports.

Significance

We assessed the effects of air pollution and greenhouse gases on public health, climate, and the hydrologic cycle. We combined a global atmospheric chemistry–climate model with air pollution exposure functions, based on an unmatched large number of cohort studies in many countries. We find that fossil-fuel-related emissions account for about 65% of the excess mortality rate attributable to air pollution, and 70% of the climate cooling by anthropogenic aerosols. We conclude that to save millions of lives and restore aerosol-perturbed rainfall patterns, while limiting global warming to 2 °C, a rapid phaseout of fossil-fuel-related emissions and major reductions of other anthropogenic sources are needed.

Abstract

Anthropogenic greenhouse gases and aerosols are associated with climate change and human health risks. We used a global model to estimate the climate and public health outcomes attributable to fossil fuel use, indicating the potential benefits of a phaseout. We show that it can avoid an excess mortality rate of 3.61 (2.96–4.21) million per year from outdoor air pollution worldwide. This could be up to 5.55 (4.52–6.52) million per year by additionally controlling nonfossil anthropogenic sources. Globally, fossil-fuel-related emissions account for about 65% of the excess mortality, and 70% of the climate cooling by anthropogenic aerosols. The chemical influence of air pollution on aeolian dust contributes to the aerosol cooling. Because aerosols affect the hydrologic cycle, removing the anthropogenic emissions in the model increases rainfall by 10–70% over densely populated regions in India and 10–30% over northern China, and by 10–40% over Central America, West Africa, and the drought-prone Sahel, thus contributing to water and food security. Since aerosols mask the anthropogenic rise in global temperature, removing fossil-fuel-generated particles liberates 0.51(±0.03) °C and all pollution particles 0.73(±0.03) °C warming, reaching around 2 °C over North America and Northeast Asia. The steep temperature increase from removing aerosols can be moderated to about 0.36(±0.06) °C globally by the simultaneous reduction of tropospheric ozone and methane. We conclude that a rapid phaseout of fossil-fuel-related emissions and major reductions of other anthropogenic sources are needed to save millions of lives, restore aerosol-perturbed rainfall patterns, and limit global warming to 2 °C.

Fracking linked to increased hospitalizations for skin, genital and urinary issues

Unconventional natural gas development and hospitalizations: evidence from Pennsylvania, United States, 2003–2014

According to a new study, rashes, urinary tract infections, and kidney stones requiring hospital stays are more common in areas with more drilling, Environmental Health News reports.

Highlights

  • Long-term exposure to unconventional drilling may be harmful to population health.
  • Genitourinary and skin-related hospitalization rates increase with drilling.
  • Healthcare professionals should encourage exposed individuals to seek care early.
  • Research into the causal mechanisms is warranted.

Abstract

Objectives
To examine relationships between short-term and long-term exposures to unconventional natural gas development, commonly known as fracking, and county hospitalization rates for a variety of broad disease categories.

Study design
This is an ecological study based on county-level data for Pennsylvania, United States, 2003–2014.

Methods
We estimated multivariate regressions with county and year fixed effects, using two 12-year panels: all 67 Pennsylvania counties and 54 counties that are not large metropolitan.

Results
After correcting for multiple comparisons, we found a positive association of cumulative well density (per km2) with genitourinary hospitalization rates. When large metropolitan counties were excluded, this relationship persisted, and positive associations of skin-related hospitalization rates with cumulative well count and well density were observed. The association with genitourinary hospitalization rates is driven by females in 20–64 years group, particularly for kidney infections, calculus of ureter, and urinary tract infection. Contemporaneous wells drilled were not significantly associated with hospitalizations after adjustment for multiple comparisons.

Conclusions
Our study shows that long-term exposure to unconventional gas development may have an impact on prevalence of hospitalizations for certain diseases in the affected populations and identifies areas of future research on unconventional gas development and health.

The early-life exposome: Description and patterns in six European countries

Exploring the exposome: study measures multitude of environmental influences on health

Scientists have measured how children and pregnant women are exposed to over 120 environmental factors influencing our health — from air and noise pollution to green space and access to public transport.

The study gathered and analysed data from six European countries to build a picture of the ‘exposome’ — the array of environmental factors that humans are exposed to from the moment they are conceived.

A better understanding of the exposome could help us understand the role of the environment in the onset of various diseases, including cancer and other chronic disorders such as cardiovascular disease. Reference.

Highlights

  • The early-life exposome is high dimensional and not easily reducible to fewer components.
  • Correlations between exposures within the same exposure group can be high.
  • Correlations between exposures in different exposure groups are low.
  • The exposome varies strongly by location and by life period.

Abstract

Characterization of the “exposome”, the set of all environmental factors that one is exposed to from conception onwards, has been advocated to better understand the role of environmental factors on chronic diseases.

Here, we aimed to describe the early-life exposome. Specifically, we focused on the correlations between multiple environmental exposures, their patterns and their variability across European regions and across time (pregnancy and childhood periods). We relied on the Human Early-Life Exposome (HELIX) project, in which 87 environmental exposures during pregnancy and 122 during the childhood period (grouped in 19 exposure groups) were assessed in 1301 pregnant mothers and their children at 6–11 years in 6 European birth cohorts.

Some correlations between exposures in the same exposure group reached high values above 0.8. The median correlation within exposure groups was >0.3 for many exposure groups, reaching 0.69 for water disinfection by products in pregnancy and 0.67 for the meteorological group in childhood. Median correlations between different exposure groups rarely reached 0.3. Some correlations were driven by cohort-level associations (e.g. air pollution and chemicals). Ten principal components explained 45% and 39% of the total variance in the pregnancy and childhood exposome, respectively, while 65 and 90 components were required to explain 95% of the exposome variability. Correlations between maternal (pregnancy) and childhood exposures were high (>0.6) for most exposures modeled at the residential address (e.g. air pollution), but were much lower and even close to zero for some chemical exposures.

In conclusion, the early life exposome was high dimensional, meaning that it cannot easily be measured by or reduced to fewer components. Correlations between exposures from different exposure groups were much lower than within exposure groups, which have important implications for co-exposure confounding in multiple exposure studies. Also, we observed the early life exposome to be variable over time and to vary by cohort, so measurements at one time point or one place will not capture its complexities.

Evidence that Pesticide Active Substances are Transported Through Air

New study results prove a significant transport of pesticides over distances of many kilometres up to remote side valleys

Gone with the wind

Measurement of pesticides in the air in Vinschgau in 2018

Task

If pesticides are used in agriculture, they never end up in their target location one hundred percent. A part remains in the ground, reaches waters or is carried away through the air by wind and thermals. In orchards, characteristic for the landscape of the Vinschgau Valley in Italy‘s German speaking province South Tyrol, this transport of particles through the air is a particularly serious problem as the spraying isn’t only done from top to bottom, but also sideways into the trees.

The aim of the study was to measure this effect to

  • provide evidence that pesticide active substances are transported through air
  • trace the spatial distribution of the various active substances
  • trace the temporal distribution of the various active substances during one growing season.

Method

Two passive collectors (TE-200-PAS) produced by the company Tisch Environment were set up at each of the four locations with very different exposure scenarios and fitted with matching disks of polyurethane foam. The material is characterised by a large internal surface on which volatilised organic pollutants can adsorb.

This method was developed in the Canadian Ministry of Environment and has been used worldwide for many years, for example in the Global Atmospheric Passive Sampling Network. The use of the standardised collection medium enables a comparison between the pollution of the locations with an active substance when compared to each other and over a course of time.

The disks were purified in a laboratory before use to prevent pollutants from distorting the results. They were replaced every three weeks and sent to a laboratory for analysis in cooling boxes by express delivery. There they were extracted with methanol and the eluate was analysed for a total of 29 pesticide active substances that would probably be used in the region.

Locations

The four locations were selected in such a way that different levels of air pollution with pesticides could be expected due to different exposure scenarios. The specific locations were as follows:

  1. A garden within the closed village of Mals/Malles Venosta. The location is relatively well protected because the property is surrounded by a hedge and there are further buildings around the property. The location was selected to determine whether spray drift is detectable in built-up areas and at the edge of the fruit production core area.
  2. The second location was chosen as centrally as possible in an orchard in the central Vinschgau. The orchard is cultivated according to biological criteria, but is located in the immediate vicinity of conventional orchards.
  3. A third location was chosen remote from inhabited or cultivated areas above the valley floor in a side valley. The selected site is a slope near a stream course at the road from the village of Burgeis to Schlinig.
  4. Finally, a location was chosen where a lot of spray drift was to be expected without pesticides being used on the site itself. For this purpose, the two collectors were set up on a further organic farm in the central Vinschgau in such a way that air from the surroundings could very well flow into them.

Results

Further results are as follows:

  • In the first measurement period from 23rd February to 16th March none of the 29 active substances was detected at any of the four locations.
  • In the following eight measurement periods a total of 20 active substances was detected and up to 14 different substances were found in one sample at the same time.
  • The more distant the site is from the conventional orchards, the lower the amount and number of active substances detected. The highest pollution could be found at site D, followed by B, A and C.
  • Six active substances were detected at all four locations: fluazinam, captan, phosmet, chlorpyrifos-methyl, dithianon und imidacloprid. This indicates an intensive use and a significant potential of transport through air.
  • Six further active substances are found at the three locations D, B and A: dodin, penconazole, cyprodinil, difenoconazole, thiacloprid and etofenprox. So they are even detectable in the air in the village of Mals in a fairly well protected environment.

Many of the pesticides that have been detected in the samples represent a significant threat to humans and the environment. Thus, for example

  • captan is labeled with H351 (“suspected of causing cancer”) in the hazard classification of the EU Pesticides Database.
  • The insecticide thiacloprid, besides being suspected of causing cancer, is classified as “May damage fertility” and “May damage the unborn child” (H360FD) and is closely monitored by the EU Commission because it interferes with the human hormone system.
  • imidacloprid is extremely toxic to bees and other insects. The median lethal dose for individual honeybees was stated to be 3.8 ng in the authorisation procedure.

Conclusion

Overall, the results prove a significant transport of pesticides over distances of many kilometres up to remote side valleys.

The results provide a clear indication of the difficult conditions for organic farms in the vicinity of intensive, conventional apple orchards.

In addition, the results point out a risk aspect that has been underestimated up to now: Compared to individual active substances, the overall pollution with pesticides causes a significantly higher exposure that continues to exist over the course of the season and thus a correspondingly higher risk potential.

Reference.

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