Chemicals in household and industrial products that disrupt the human hormone system are linked to high global rates of breast, ovarian, prostate, testicular and thyroid cancers, warns a report released today by the UN Environment Programme and the World Health Organization.
Endocrine disrupting chemicals, or EDCs, can occur naturally, while synthetic varieties are found in pesticides, electronics, personal care products and cosmetics. They can also be found as additives or contaminants in food.
The report also links EDCs to childrens' health issues such as non-descended testes in young males, developmental effects on the nervous system and attention deficit hyperactivity.
"Close to 800 chemicals are known or suspected to be capable of interfering with hormone receptors. However, only a small fraction of these chemicals have been investigated in tests," states the report. "The vast majority of chemicals in current commercial use have not been tested at all."
EDCs enter the environment mainly through industrial and urban discharges, agricultural run-off and the burning and release of waste. People are exposed when they ingest contaminated food, dust and water, inhale gases and particles in the air, or make skin contact with contaminated substances.
"We urgently need more research to obtain a fuller picture of the health and environment impacts of endocrine disruptors," said Dr. Maria Neira, the World Health Organization's director for public health and environment.
"The latest science shows that communities across the globe are being exposed to EDCs, and their associated risks," she said.
Human health depends on a well-functioning endocrine system to regulate the release of certain hormones that are essential for functions such as metabolism, growth and development, sleep and mood. Endocrine disruptors can alter the functions of this hormonal system, increasing the risk of adverse health effects.
Many endocrine-related diseases and disorders are on the rise. According to the report:
- Large proportions (up to 40 percent) of young men in some countries have low semen quality, which reduces their ability to father children.
- The incidence of genital malformations, such as non-descending testes and penile malformations, in baby boys has increased.
- The incidence of adverse pregnancy outcomes, such as preterm birth and low birth weight, has increased in many countries.
- Neurobehavioural disorders associated with thyroid disruption affect a high proportion of children in some countries and have increased over past decades.
- Global rates of endocrine-related cancers – breast, endometrial, ovarian, prostate, testicular and thyroid – have been increasing over the past 40 to 50 years.
- There is a trend towards earlier onset of breast development in young girls in all countries where this has been studied. This is a risk factor for breast cancer.
- The prevalence of obesity and type 2 diabetes has dramatically increased worldwide over the last 40 years. WHO estimates that 1.5 billion adults worldwide are overweight or obese and that the number with type 2 diabetes increased from 153 million to 347 million between 1980 and 2008.
"Investing in new testing methods and research can enhance understanding of the costs of exposure to EDCs, and assist in reducing risks, maximizing benefits and spotlighting more intelligent options and alternatives that reflect a transition to a green economy," said Steiner.
Wild animals are also affected by exposure to EDCs. Population declines in species of otters and sea lions may also be linked to their exposure to mixtures of PCBs, the insecticide DDT, other persistent organic pollutants, and metals such as mercury.
"Research has made great strides in the last ten years showing endocrine disruption to be far more extensive and complicated than realized a decade ago," said Professor Ake Bergman of Stockholm University and chief editor of the report.
"As science continues to advance, it is time for both management of endocrine disrupting chemicals and further research on exposure and effects of these chemicals in wildlife and humans."