You may never have heard of Percival Pott ... but you can bet that every chimney sweep the world over can thank this 18th century British surgeon for saving his scrotum.
Chimney sweeps and scrotums might seem like an odd place to start a discussion of this year's lecture by Dr. Irena Buka, director of the Pediatric Environmental Health Specialty Unit (PEHSU) in Edmonton. But Buka's description of Pott, the first doctor to forge a link between soot exposure and scrotal cancer, was a noteworthy starting point for her talk on pediatrics and the environment.
With the audience captivated by Pott’s story, Buka explained that it took researchers 200 years to isolate the polycyclic compound in soot (3,4-benzpyrene) linked to scrotal growths. These growths frequently developed in chimney sweeps.
In 1775, without the help of advanced cell theory, there were no chemical tests to back up Pott’s suspicion of a connection. Still, a randomized trial in which some boys bathed after being covered in soot, while others did not, demonstrated that toxins in soot were the culprit. He showed that this cancer could be largely prevented with a good bath. As a result, a series of British Chimney Sweep Acts were implemented to protect young apprentices, forcing employers to provide them with baths.
Pott’s story is worth recounting and not just because his efforts were a coup for occupational health. Historically, it showcases the fact that pediatric studies of the environment are nothing new. And it cuts straight to the heart of the question raised by Dr. Buka in her lecture, “Children & Environmental Exposures in Canada: Do our kids need protection from carcinogens?”
The answer is a resounding ‘yes’: kids do need protection. If protective policies could be enforced based on Pott’s general findings, we could be doing more today to protect children from toxic dangers before they become tomorrow’s cancer patients.
This is where Dr. Buka’s research is crucial. As a pediatrician with over 20 years of clinical experience, she works with the World Health Organization (WHO) in the area of biomarkers, also serving on WHO’s consultative group for building capacity in pediatric environmental health training.
Her clinical investigations focus on a gamut of risk factors—physical, psycho-emotional, chemical, biological, and socioeconomic, affecting fetal and childhood development
—and include autism, birth defects like cleft palate, and asthma.
While Buka’s interests go beyond specific carcinogens, she quickly pointed out the core connection between BCAM’s goals and her pediatric interests. “There are a number of new driving forces and global environmental changes posing challenges to human health,” she explained, “These challenges contribute to environmental degradation, which disproportionately affects children. Children are the next group of procreators and decision- makers,” she added, asserting that controlling pediatric environmental hazards can help to prevent health risks over a lifetime, including breast cancer.
Dr. Buka showed us some dire consequences of hazardous environmental exposures during childhood. These included radiation after the bombing of Hiroshima and the Chernobyl disaster. Survivors of both tragedies had higher rates of adult-onset breast cancer.
Obviously, Hiroshima and Chernobyl are extreme examples. But when Buka gave a more detailed picture of the complex and unique physiology involved in child development, the environmental dangers facing today’s kids seem no less dramatic. The developing fetus and child have distinct exposure risks, she explained, making their bodies obvious receptacles for toxins. A child’s fundamental anabolic need for more calories and water, for example, expose them to more dangerous substances.
“Kids need more calories and more water per unit of body weight than adults,” Buka explained. “Toxicants carried in food will be delivered at a rate 2-3 times higher in children than in adults. Water is delivered at 5-7 times the adult rate. Children also have more restricted diets with a higher proportion of fruits and vegetables. Pollutants such as pesticides in these foods are likely to be delivered in higher quantities to children.”
Because of their unique body-surface-to-volume ratio, and the nature of their respiratory development, kids inhale more pollutants per kilogram of body weight than adults. “Children breathe more quickly. An infant has three times the minute ventilation of an adult. A 6-year-old has double. Environmental toxicants found in the air, both indoors and out, will be delivered to children at higher rates.” The toxicants include ozone, oxides of nitrogen, and particulate matter. Other dangers are lead, mercury, as well as moulds and volatile organic compounds.
Children also run the risk of absorbing more substances through the skin. Their eating habits and exposure to hazards are largely involuntary, including those derived from ingestion such as teething. “Kids,” Buka reminded us, “can’t exactly remove themselves from danger.”
Even children’s small statures put them at risk in a household setting, where dust particles and pet dander settle on the floor—the place where babies do their crawling. Worse still, a lot of household dust and residue settles at adult knee-level. As they complete the growth cycle, this is precisely the height at which youngsters are most active.
She gave other examples of recent scares involving high levels of lead in children’s toys, phthalates found in the urine of infants exposed to certain baby products, and respiratory illnesses in urban areas with high levels of emissions from car exhaust.
So what’s being done to monitor and control potential toxins?
As the director of Edmonton’s PEHSU, the only Canadian clinic of its kind, Dr. Buka collaborates with U.S. and Mexican clinics tracking and studying pediatric environmental illnesses. Their mandate is to provide environmental assessments, care, and education to children at risk.
Canada’s National Pollutant Release Inventory (NPRI) also registers 8,000 industrial facilities emitting potential toxins. They have information on approximately 300 chemicals, air pollutants, carcinogens, neurotoxins and teratogens (substances that cross the placental barrier and harm the fetus). But there’s still a long way to go before ensuring sufficient regulation of chemicals in our air, food, and water. “What we monitor is the tip of the iceberg,” Buka told the audience. “The majority of the chemicals we’re talking about aren’t even monitored.”
So let’s return to the story of Dr. Pott. Even in the absence of advanced chemical tests to back him up, Pott was able to promote prevention by doing detective work demonstrating the relationship between toxins and disease. Buka insists that we can do the same by staying vigilant and informed. We need to empower our communities with increased access to information, and push for protective policies. And she urges, we must do more to monitor the chemical dangers surrounding our kids.
- Tips from the Pediatric Environmental Health Specialty Unit (PEHSU) www.aoec.org/pehsu/
- David Suzuki Foundation’s The Food We Eat: an International comparison of Pesticide Regulations www.davidsuzuki.org
- The US Environmental Protection Agency, Toxicity and Exposure Assessment for Children’s Health (TEACH) www.epa.gov/teach/
- US Agency for Toxic Substances and Disease Registry (ATSDR): Toxicological Profiles http://toxprof.crcpress.com
- The National Pollutant Release Inventory and Air quality advisories www.ec.gc.ca/inrp-npri/
Some Tips for Parents
- Consider organic foods
- Be familiar with fish advisories (for levels of mercury)
- Avoid the middle aisles of the grocery store, where processed food is displayed
- Read labels on prepared food (minimizing intake of processed foods with dyes and preservatives)
- Avoid alcohol (during pregnancy)
- Cut fat from meat
- Protect children from non-nutritive digestion particularly during teething; watch for babies gumming or chewing objects with potential toxicants
- Avoid bottled water (due to bisphenol A)
- Avoid sprays
- Use eco-friendly cleaning and personal care products