Disinfection & downstream effects

Gender and the Implications of Pharmaceuticals and Personal Care Products in our Water

Trace levels of pharmaceuticals and personal care products (PPCPs) are presently found in Canadian surface water and groundwater, and drinking water. Indeed, these compounds are starting to be acknowledged as pollutants that are persistent in our environment. Their ‘persistence’ is thought to derive not only from chemical properties that resist their breakdown in the environment, but from their continuous, and growing, release. Because only a fraction of ingested drugs are completely broken down by the human body, a portion of these drugs and their metabolites enter our waterways daily, along with the compounds from the myriad of personal care products – shampoos, soaps, creams, gels, detergents – routinely washed down the drain. Pharmaceuticals also enter the environment via agriculture, aquaculture, hospital effluent and manufacturing plants. At present, neither wastewater nor drinking water treatment facilities are designed to completely remove these products, which results in their persistent release into Canada’s lakes, rivers and streams. While the concentration of PPCPs in the environment is very low, researchers and policy makers in Canada and internationally have expressed a concern that these chemicals have the potential to harm ecosystems and human health over the long-term. Box 1 lists the PPCPs that have been found in Canadian drinking water. Routine data are lacking however, since PPCPs are not included in current drinking water guidelines nor are they tested for in drinking water treatment facilities. Around the world, well over 30 different types of PPCPs have been found in drinking water.

Not only may we be chronically exposed to trace levels of PPCPs in our water but the presence of PPCPs in drinking water creates another problem: PPCPs can react with the chemicals used to disinfect our water to form additional chemical by-products. Already, a wide range of disinfection by-products (over 600 have been identified) are created when disinfectants such as chlorine react with naturally-occurring organic matter found in water. While the evidence is inconclusive, studies have linked exposure to disinfection by-products to a range of adverse health effects including certain forms of cancer and reproductive health outcomes. Emerging research shows that PPCPs, too, can react with the same disinfectants. For example, new chemical by-products, often of unknown properties and toxicity, are created when disinfectants mix with common PPCPs, such as the estrogenic steroids used in contraceptives, anti-inflammatory agents such as ibuprofen, the antibacterial agent triclosan, and ultraviolet (UV) filters.

Clearly, disinfection promotes public health by killing pathogens in drinking water.  And yet, the formation of disinfection by-products, particularly those derived from PPCPs points to the limitations of technological solutions for controlling contaminants in drinking water.

What does a sex and gender analysis (SGBA) of the problem reveal?

Important questions of sex and gender do not feature in current analyses of PPCPs in the environment, despite the obviously gendered patterns of use for many pharmaceuticals (e.g., contraceptives, hormone therapy, anti-depressants) and personal care products (cosmetics, sunscreens, perfumes), and the possible sex and gender-related disparities in health effects of exposures to trace levels of these contaminants and disinfection by-products, in drinking water.   

Gendered use of PPCPs

Many of the PPCPs detected in the environment are used in different ways, and in vastly different quantities, by men and women. This is true both for pharmaceuticals and for personal care products. Women consume more pharmaceuticals than men, for reasons that are both biological and social. Contraceptives, fertility drugs and menopausal hormones are prescribed exclusively to women, and many women are on some form of hormonal medication throughout their lives, from puberty onwards. Women are also diagnosed with psychiatric problems such as depression and anxiety more often than men and are more likely than men to be prescribed anti-depressants for similar symptoms of emotional distress.

Personal care products (PCPs) are distinct from pharmaceuticals in a number of ways. PCPs are generally meant to be safely used by healthy people. PCPs include such a large and varied range of products that discussing gendered use in relation to particular chemical ingredients is not self-eviden. Some popular products are clearly used predominantly by women, however. For example, the overwhelming majority of users of ultraviolet (UV) filters - the chemicals used in the production of sunscreens - are women; the same is true for many other products (creams, lotions, cosmetics, etc) that now commonly contain UV filtering compounds. Synthetic musks – the chemicals used as fragrance materials in a wide range of consumer products including perfumes, soaps, lotions, shampoos, and laundry detergents - also have distinctly gendered patterns of use.  

Gendered exposures to PPCPs

Assessing gendered exposures to PPCPs in drinking water is difficult given the paucity of data available on PPCPs in the environment broadly, and gender based data specifically. Do women drink more or less water than men? Are women’s places of residence – clearly a factor in determining drinking water quality – distributed differently than men’s? Answers to such questions would provide better insight into gender differences in exposure. The exposure of pregnant women to PPCPs in drinking water is one area where some data are available. For example, the recommendation that pregnant women drink two litres of water of per day, if followed, might expose this group to more contaminants than someone drinking less over an equivalent period. Indeed, one estimate found that following the two litre/day guideline might expose a pregnant woman to five drugs of particular concern during her pregnancy.

Gendered health effects of PPCPs in drinking water

Many PPCPs, including oral contraceptives, hormone therapies, anti-epileptics, anti-inflammatory drugs, some anti-depressants, UV filters, and synthetic musk fragrances, are considered endocrine disruptors. At this stage, evidence of gendered health effects of PPCPs is drawn primarily from research examining the impact of endocrine-disrupting chemicals on aquatic species. A common finding among such studies is the feminization of male fish, which manifests as arrested testicular development and the production of early-stage eggs in their testes. When researchers added low concentrations of ethinylestradiol to a Northern Ontario lake, for instance, male fathead minnows were feminized and egg formation in females was altered, leading to near-extinction of the species in that lake. Intersex fish have attracted attention because reproductive changes observed in fish are comparable to effects, such as testicular dysgenesis syndrome, observed in humans. Clues to possible effects can also be gleaned from research on pesticides and industrial contaminants which suggests that ongoing in utero and early childhood exposures to compounds classified as endocrine disruptors may well have gendered health effects.

Why worry about trace levels?

Compared to the daily therapeutic dosages of a pharmaceutical drug, the concentrations of any particular drug present in the aquatic environment is very low. As a result, some analysts conclude that the risk to human health from the trace amounts detected in Canadian drinking water samples is negligible because “an individual would have to consume thousands of glasses of drinking water a day to reach the maximum acceptable daily intake”. Research on the category of substances known as endocrine disruptors suggests otherwise.

Based on understandings from the new field of epigenetics, endocrine disrupting compounds interact with the body’s endocrine signalling systems in a way that makes not only dosage but also timing critical in determining the effects of exposure. Epigenetic alterations reprogram the regulation of vital cellular functions, allowing the organism’s organ systems to adapt to stresses in the environment, including exposures to hormones, drugs or toxins, and thereby prepare the organism for meeting similar demands in later life. This reprogramming or imprinting takes place at critical periods or “windows” in the development of organ systems. In humans, these periods occur during fetal development, childhood and, for the reproductive and central nervous systems, continue into late adolescence. Synthetic chemicals that mimic internal cues have the capacity to confuse this adaptive system, increasing the risk of diseases later in life. Thus, exposure to chronic low levels of endocrine disruptors in the environment might well have human health effects; stage of development would be highly relevant; and significant interactions among substances might be expected.

Concerns about the human health effects of PPCPs in the environment are not restricted to endocrine disruptors, however. All pharmaceutically active compounds are developed to target specific biological activity and are not meant for dispersion into the environment. It is for good reasons that many pharmaceuticals are available only with a prescription, specifically because they are not appropriate for everyone, or for widespread or long-term use. In contrast to pharmaceuticals, personal care products are not designed for human consumption at all. Very little is known about the potential health effects of chronic ingestion of these compounds; as with pharmaceuticals, however, their presence in drinking water, even at very low levels, raises important questions for long-term population health.

Looking upstream: a neglected part of the solution

For some, the solution to PPCPs in drinking water rests with improved water treatment systems. While such technologies are an important element to control the levels of PPCPs in drinking water, they cannot be the only strategy, for several reasons. First, advanced treatment technologies such as ozonation are costly, and are therefore likely to remain inaccessible to most Canadians who continue to rely on chlorine to disinfect their water. Second, even the best technologies are unable to completely remove all contaminants, and worse, as noted above they can create additional by-products, seldom accounted for when assessing the merits of such treatments. Ozonation of the anti-convulsant drug carbamazepine, for instance, has been found to yield three new and previously unreported by-products. Given that new PPCPs are constantly becoming available in the marketplace, it becomes questionable whether treatment technologies will be able to keep pace.   
Rather, such “end of pipe” solutions should be coupled with strategies for reducing the load of PPCPs entering into the environment in the first place. Taking a preventative or “upstream” approach recognizes that while the risks posed by such substances may not be entirely known, it is better to err on the side of caution. Moreover, many upstream steps could be implemented immediately and relatively cheaply, when compared to the longer term investments required for broad scale improvements to drinking water treatment plants.

While many PPCPs serve essential, life-affirming ends, there are also cases where the use of some products could be curtailed or eliminated altogether. One example is the proliferation of antibacterial products such as hand soaps, many of which contain triclosan – a substance now found widely in the environment, including in drinking water. Despite their popularity, the use of antibacterial products for regular hand washing is not recommended by Health Canada, the Canadian Medical Association, or the Canadian Paediatric Society.        
     
And yet, current PPCP use and promotion trends point in the opposite direction.  Canadians are consuming more and more drugs each year. For their part, pharmaceutical companies are delivering drugs in more aggressive and ever inventive ways, often with specific campaigns that target women and exploit gender roles.

Some upstream strategies to consider might include:

• Reducing pharmaceutical use by strengthening the direct-to-consumer advertising ban in Canada. At present, enforcement is woefully inadequate;
• Stemming the tide of pharmaceutical inputs to aquatic systems by broadening consumer pharmaceutical take-back programs. Programs exist in a handful of provinces.  More should follow suit;
• Better education of consumers, including young people, patients, physicians and pharmacists about the environmental consequences of improper disposal and misuse of PPCPs; and   
• Judiciously curbing the use and promotion of some PPCPs.

Clearly, practical and realistic steps can be taken immediately to curb the release of PPCPs into the environment. A sex and gender based analysis reveals that attention to the impact on women is a critical aspect in such efforts.    

Sharon Batt is a founding member of Breast Cancer Action Montreal and author of Patient no More: The Politics of Breast Cancer.