Experts urge increased attention to the threat of climate change and pollution on children's health

A new paper published in the Global Pediatrics Journal explores the impact of climate change and environmental chemicals that disrupt endocrine function on children's health.

Study: The effects of climate change and exposure to endocrine disrupting chemicals on children's health: a challenge for pediatricians. Image Credit: Tartila/Shutterstock.com

Background

The last few decades have witnessed multiple crises involving the economy, public health (the coronavirus disease 2019 pandemic), and the natural environment.

Children are among the most severely affected by such crises the world over.

Children and climate-linked disasters

Recently, the planet has suffered extreme weather events, air pollution, airborne allergens, heat waves, drought, and a poor-quality diet, at increasing frequency.

In contrast to mere disaster management, the world needs to learn from past crisis experiences, which helps inform strategies and policies in pediatric public health.

Both climate change and pollution harm children's health significantly. Over 300,000 children have died in natural and climate-related disasters.

Almost $3,000 billion has been lost directly because of natural disasters. Over three-quarters of these are due to climate-related causes.

More than seven-eighths of people affected by diseases resulting from climate change are children. Scientists estimate that over 170 million children are traumatized by climate-related disasters, while many are at serious risk for death or severe injury.

The most at-risk are typically those from a lower socioeconomic class since they are the least able to adapt, escape, or mitigate the adverse impacts of these factors.

Children's health and environmental pollution

Recent initiatives to promote children's health by preventing the consumption of endocrine-disrupting chemicals (EDCs) and other toxins present in food include the European Union (EU)-funded Safe Food For Infants (SAFFI) project.

Children are more susceptible to environmental pollution because of the higher proportion of food-, air-, and water-to-body weight intake ratio. The immature blood-brain barrier also allows greater brain exposure to toxins that may cause neurological damage.

In addition, children also have more sensitive skin that is more permeable to allergens, toxins, and microbes.

Furthermore, children spend much time in contact with EDCs in toys, carpets, and furniture padding. The immature developmental stage of pediatric organs and organ systems reduces detoxification efficiency.

Unfortunately, people know little about these risks and are not on the alert to reduce such exposures.

How EDCs affect children

EDCs can alter endocrine function and thus cause harm to organisms or their progeny. Of the current total of about 140,000 chemicals produced today, about 800 are considered EDCs, but few have been explored in detail.

Many EDCs are found in household or everyday objects, including furniture, clothing, upholstery, building materials, cosmetics, personal care products, and foods and/or containers.

While the oral consumption of EDCs is the most important, these chemicals can also enter via the air or the skin. Food contact materials (FCMs) are key to such exposures, being present from the production stage to serving food.

Currently, about 175 chemicals are known to migrate into food from FCMs, very few of which have been studied in depth.

EDCs are known to be sex steroid receptor antagonists or agonists. For instance, they may cause excessively high estrogen or abnormally low androgen activity.

This may, in turn, cause abnormal development of the male reproductive system and interfere with fertility, as well as a higher risk of in situ testicular carcinoma.

EDCs may also act on other hormone receptors, altering their concentrations, inhibiting hormone synthesis, and binding to their transport proteins. Free hormones are vulnerable to breakdown, which may cause reduced hormone activity.

Neurotransmitter synthesis may also be affected, resulting in abnormal neurodevelopment. These chemicals are sometimes considered "endocrine and nerve disruptors" (ENDs) rather than just EDCs.  

These are also metabolic disruptors. ENDs are associated with metabolic syndrome, type 2 diabetes, and insulin resistance. They also promote obesity and may act through multiple pathways to dysregulate hunger, insulin responses, fat synthesis, and energy metabolism.

A fat cell receptor called proliferator-activated receptor gamma, PPARγ, also found on liver and intestinal cells, is known to be bound and activated by the commonly found EDC, bisphenol A (BPA). Thus, it can interact with these key metabolic pathways.

Finally, epigenetic pathways could also be affected by EDCs, which could thus alter embryonic development and differentiation. This may underlie an increased and heritable metabolic disease risk in adult life.

Sources of EDCs

EDCs may be ingested through food via contamination, processing, adulteration, additives, and leaching from food packaging. Pesticides and cleaning chemicals, including persistent organic pollutants (POPs), are common environmental contaminants that can enter the food chain.

POPs have a place of their own among EDCs. They were defined by the Stockholm Convention (2004) and showed bioaccumulation in human tissues since humans are the apex species.

POPs have been studied in some detail. They are metabolized slowly at higher concentrations and are obesogenic, as well as being EDCs.

They are stored within the fat deposits and thus released slowly over time, contributing to continued exposure even after environmental or exogenous exposure ceases. 

It is important to focus on phthalates, perfluoroalkyl substances (PFAS), BPA, and triclosan, because of their wide use in consumer products and wide spectrum of activity on the metabolic and endocrine processes of the human body.

Most research on these compounds is limited to animal studies, and epidemiological studies in humans are limited to single compounds for the most part.

Among the key effects of specific POPs, organochlorine pesticides can cause neurologic damage and act as EDCs/ENDs; polyaromatic hydrocarbons cause mutations; polybrominated diphenyl ethers are linked to reproductive tract cancer; perfluorinated compounds to breast cancer; and dioxins or furans to neurodevelopmental and metabolic disorders. All these have a wide spectrum of phenotypes.

What are the implications?

The scientists recommend that pediatricians be familiar with environmental health, helping to reduce exposure to these harmful substances that strongly impact children's health via multiple mechanisms.

Apart from increasing public recognition of and participation in framing policies on environmental health…

…pediatricians must take an active role in recognizing diseases associated with climate change and environmental pollution and develop early warning systems."

Written by

Dr. Liji Thomas

Dr. Liji Thomas is an OB-GYN, who graduated from the Government Medical College, University of Calicut, Kerala, in 2001. Liji practiced as a full-time consultant in obstetrics/gynecology in a private hospital for a few years following her graduation. She has counseled hundreds of patients facing issues from pregnancy-related problems and infertility, and has been in charge of over 2,000 deliveries, striving always to achieve a normal delivery rather than operative.