Editor’s note: This month, we are exploring “how science can build a sustainable future” – revealing opportunities we may not have considered. For World Environment Day June 5, we present research that has implications for global environmental health.
Sometimes in a bid to protect ourselves from nature’s dangers, we inadvertently increase our risk of harm. In the 1970s, homes around the world were being protected from fire with flame retardant chemicals called polybrominated diphenyl ethers (PBDEs). Found in almost everything, from carpets to stereos, PBDEs soon became ubiquitous in people’s homes.
But evidence emerged showing that PBDEs, which last a long time in the environment, are toxic and potentially harmful to brain development. In 2004, manufacturers started using alternatives – TBB and TBPH – and PBDEs were gradually phased out by 2013. Although we know relatively little about the health effects of the alternative flame retardants, they have been linked to hormone disruption and reduced fertility in rodents.
Despite their known and potential harmful effects, all three chemicals are still found in homes, detectable in dust particles as well as in the products they were designed to protect. This poses a particular problem for children: toddlers crawl on the floor and climb on furniture, putting them in constant contact with the chemicals.
Now, a study in Emerging Contaminants reveals the extent of the contamination, with the chemicals found in 100 percent of homes in New York – and on the hands of the toddlers living in them. The journal is published by KeAi, a joint venture of Elsevier and China Science Publishing & Media (CSPM).
According to the American Chemical Council, flame retardants work in three main ways at different points of the fire cycle:
- They can stop a fire from being ignited or prevent dangerous bursts of flames.
- They can form a protective layer keeping the fire away from the material.
- They can dilute flammable gases by producing water, nitrogen or other non-reactive gases when a fire occurs.
Flame retardants are intended to keep us safe, but there are many non-chemical fire safety options, such as sprinklers, flameless candles, fire-safe cigarettes, smoke detectors and naturally flame resistant products like wool. What if the flame retardant chemicals were having a significant – but not so visible – effect on our health, and that of our children?
The extent to which young children are exposed to these chemicals is cause for concern given the known neurodevelopmental risk of PBDEs and the potential toxicity of their substitutes. Exposure to these chemicals is ubiquitous and it primarily occurs through ingestion of dust, placing young children, who spend increased amounts of time on the floor and engage in hand to mouth activity, at risk for elevated exposure.
For their study, Dr. Herbstman and her colleagues at Colombia and Duke University in North Carolina visited the homes of 25 mothers and children who were enrolled on the CCCEH Sibling-Hermanos birth cohort, which started in 2008.
When the children were 3 years old, the team took samples using hand wipes from the mothers’ and children’s hands and collected dust from their homes. They found that both PBDEs and the newer brominated flame-retardants, TBB and TBPH, were detected in every house dust sample. Worryingly, they were also found in 100 percent of the hand wipe samples.
On average, the levels of TBB and TBPH in house dust were higher than PBDEs; PBDEs and TBPH were found in every hand wipe sample; and TBB was found in 95 percent of samples. There was a correlation between the levels of flame retardant chemicals on the mother and child’s hands, but the children had higher levels than their mothers. Dr. Herbstman commented:
Toddlers are being exposed to replacement flame retardant chemicals that we know little about. Future research needs not only to focus on understanding the toxicity of these compounds, but also on how exposure occurs in the home and what behaviors and policies can be used to reduce personal exposure.
Breaking the scientific language barrier
This is the first study to compare the three flame retardants – PBDEs, TBB and TBPH – in house dust and hand wipe samples from mothers and children. Although the study was conducted in New York, the chemicals detected have been used globally for decades, making this a worldwide problem.
With global environmental health issues like this, it is important to ensure the global science community can access and read the research. Gert-Jan Geraeds, KeAi General Manager, described the role of KeAi:
Environmental issues are of great concern to Asia and China in particular. The Chinese government is stepping up their efforts and making unprecedented financial investments in fighting environmental pollution and accelerating sustainable development. At more than 20 percent over the last couple of years, China’s growth rate of published articles on sustainability science has been higher than that of any other country in the world.
KeAi, based in Beijing, is helping to increase the global visibility of that high quality research and its impact on the world. Increasingly, that research is accessible through KeAi’s open access journals on ScienceDirect. “Given the investment and growing research output China is seeing in this area, this will be crucial for the advancement of sustainability science worldwide,” Geraeds said.
In addition, KeAi provides a wide range of services to the academic community, from bibliometric analyses for Chinese society journals to author and reviewer workshops.
World Environment Day 2017 celebrates our connection to nature – something researchers are investigating around the world. KeAi has published these related articles open access:
- Shailly Kedia: Approaches to low carbon development in China and India, Advances in Climate Change Research (December 2016)
- Jian-Kun He: Global low-carbon transition and China's response strategies, Advances in Climate Change Research (December 2016)
- Ying Chen, Yuan Xin: Implications of geoengineering under the 1.5 °c target: Analysis and policy suggestions, Advances in Climate Change Research (May 2017)
- Jun Xia, Qingyun Duan, Yong Luo, Zhenghui Xie, Zhiyu Liu, Xingguo Mo: Climate Change and Water: Case Study on Eastern Monsoon Region of China, Advances in Climate Change Research (April 2017)
- He-Qin Cheng, Ji-Yu Chen: Adapting cities to sea level rise: a perspective from Chinese deltas, Advances in Climate Change Research (May 2017)
Read the study featured in this story
KeAi has published this article open access:
Cowell, Whitney et al: “Prevalence of historical and replacement brominated flame retardant chemicals in New York City homes,” Emerging Contaminants (March 2017)
Emerging Contaminants is an outlet for world-leading research addressing problems associated with environmental contamination caused by emerging contaminants and their solutions. Emerging contaminants are defined as chemicals that are not currently (or only recently) regulated and about which there exist concerns regarding their impact on human or ecological health. The journal publishes papers addressing science that facilitates greater understanding of the nature, extent, and impacts of the presence of emerging contaminants in the environment; technology that exploits original principles to reduce and control their environmental presence; as well as the development, implementation and efficacy of national and international policies to protect human health and the environment from emerging contaminants.
Dr. Julie Herbstman is Associate Professor of Environmental Health Sciences and Co-Director, Molecular Epidemiology Certificate at Colombia University in New York, USA. Trained as an epidemiologist, Dr. Julie Herbstman's research focuses on the impact of prenatal exposures to environmental pollutants, including polybrominated diphenyl ethers (PBDEs) and polycyclic aromatic hydrocarbons (PAHs) on child growth and development. She has also been involved in research exploring the long-term environmental health impact of exposure to pollutants from the collapse of the World Trade Center on 9/11. Most recently, she collaborates on the Columbia Children's Center's work involving the integration of epigenetic biomarkers to explore the mechanistic pathway between prenatal exposures and disease risk.
How science can build a sustainable future
As the US withdraws from the Paris climate agreement, sustainability science commands the world’s attention. This month, we examine the role of science in building a sustainable future and how science, technology and medicine will be instrumental in overcoming the greatest challenges facing humanity.
We open this series with a special issue for World Environment Day on the UN’s theme of “connecting people to nature.” Throughout the month, we will post more stories on this theme. You can find them here.