Exposure to chemicals can have adverse impacts on both human and wildlife reproductive systems. Reproductive effects include alterations in sexual behaviour, decreases in fertility, menstrual changes, changes in the onset of puberty, cancers of reproductive organs, miscarriage, premature birth and other effects. Sometimes the effects of exposure are not seen until the next generation. For example, when a pregnant mother is exposed to chemicals, this exposure can also impact the developing child and lead to developmental effects, such as birth defects, low birth weight, impacts on cognitive development or other harmful outcomes.
Reproductive and developmental impacts occur at varying doses and exposures to environmental chemicals. The research described below involves laboratory animal research conducted at many different dose levels, which may or may not be comparable to human exposure associated with using household cleaning products containing these chemicals. The research does, however, provide a rationale for a precautionary concern about the release and ubiquitous presence of these chemicals in our environment.
How Common are Reproductive and Developmental Effects?
Many scientists now believe that chemical exposure, even at very low levels, can have adverse impacts on the reproductive system, and important research is underway to better understand the mechanisms and consequences of chemical exposure. Despite the limited amount of data on reproductive and developmental effects in humans, what we do know raises sufficient cause for concern. For example, research indicates that there is a widespread incidence of neurobehavioural problems at birth and in childhood; birth defects involving malformations of the male reproductive tract have been increasing; breast cancer incidence has risen for decades and only recently began to decline; the incidence rate of testicular cancer in young men is rising; and declining sperm counts have been documented worldwide. While the exact chemicals or mechanisms to explain these impacts are still uncertain, they teach a precautionary lesson about our ubiquitous exposure to environmental chemicals.
Chemicals in Household Cleaning Products Linked to Reproductive and Developmental Effects
Three groups of chemicals commonly found in household cleaning products that are of concern for their potential as reproductive or developmental toxics are glycol ethers, alkyl phenol ethoxylates (APEs) and phthalates.
Glycol ethers are a large group of organic solvents widely used in cleaning chemical formulations for both industrial and household applications. Solvents are degreasing chemicals which help dissolve stains or dirt, particularly those made of fats or oils. Several glycol ethers have been identified as reproductive toxins. It is worth noting that slight differences in glycol ether structure can drastically change their toxicity. The US EPA''s hazard summary for glycol ethers states: Animal studies have reported testicular damage, reduced fertility, maternal toxicity, early embryonic death, birth defects, and delayed development from inhalation and oral exposure to the glycol ethers.
Occupational exposure to glycol ethers has also been shown to result in reproductive and developmental impacts. Studies of exposed male workers show some indication that glycol ethers can reduce sperm counts among human males. Pregnant women exposed to glycol ethers in their work environments were significantly more likely to have children with birth defects such as neural tube defects and cleft lip. A recent study in California was the first to assess exposure to glycol ethers from use in home cleaning. The study measured actual emissions of glycol ethers and other volatile organic compounds (VOCs) under normal home cleaning conditions and assessed their contribution to indoor air quality. These researchers suggest that potential exposures to VOCs such as glycol ethers like 2-butoxyethanol from home cleaning can be high enough to exceed threshold safety levels established for industrial settings. In particular, potentially dangerous levels of these chemicals were seen in smaller, poorly ventilated rooms (such as a bathroom), where floor cleaners were used in combination with air fresheners. 2-butoxyethanol is a volatile chemical which evaporates into the air as cleaning products are used. In addition to inhaling 2-butoxyethanol vapor, research has shown that skin can also absorb 2-butoxyethanol vapour from the air, making skin a major pathway of exposure to this chemical. There is widespread use of 2-butoxyethanol in household products, including glass cleaners, carpet/rug cleaners, floor cleaners and oven cleaners among others.
Alkylphenol ethoxylates (APEs) are a class of chemicals which act as surfactants. Surfactants are chemicals which get in between dirt and a surface (on a kitchen counter, a piece of fabric or even human skin), allowing water to more easily wash away the dirt. APEs are often added to laundry detergents, laundry stain removers, hard surface cleaners and all-purpose cleaners to increase their cleaning efficiency. It is estimated that half of the APEs manufactured ultimately pass through wastewater treatment systems into surface waters. APEs are of great concern, as they are the only detergent additives which become more toxic as they degrade. Nonylphenol (NP) is a breakdown product of NPEs which is known to mimic the hormone estrogen and impact the production of testosterone, both of which can have numerous reproductive and other health impacts. In female rats, exposure to nonylphenol delayed the onset of puberty and altered fertility. In male rats, octylphenol and octylphenol ethoxylate decreased testicular size and sperm production, and nonylphenol also reduced testicular size. Both octylphenol and nonylphenol stimulated the growth of human estrogen-sensitive breast cancer cells; and octylphenol was found to be ten times as potent as nonylphenol in generating this effect. A significant concern around the use of APEs centres around their impact on wildlife, particularly in aquatic ecosystems. APEs are found in rivers and sediments at levels that can cause harm to aquatic organisms such as fish, frogs and turtles. Exposure to APEs at levels as low as 3-10 micrograms/ litre reduced the number of fertilized trout eggs and caused reduced embryo survival and abnormal embryos in another fish, the Japanese Medaka. The development of leopard frog tadpoles was affected by exposure to a combination of octylphenol and UV light. APE contamination has also been found in human environments. For example, in one study, 4-nonylphenol was detected in the house dust of each of 120 homes tested. Another study showed that nonylphenol was detected in food purchased in German supermarkets. In that study, 40 kinds of adult food and 20 baby foods were tested and all samples showed some level of nonylphenol. Not surprisingly, nonylphenol is also found in humans during biomonitoring. A recent study detected nonylphenol in the urine of 51% of human volunteers tested.
Phthalates are a class of chemicals widely used in consumer products, primarily as plasticizers to make brittle plastics soft. They are also used in cosmetics and household cleaning products (in deodorizers, laundry detergents and fabric softeners). One particular type of phthalate, dibutyl phthalate (DBP), is also found in floor polish and window cleaners. It is difficult for the consumer to determine if phthalates are present in cleaners or other consumer products. Generally, phthalates are incorporated in the fragrance, the contents of which are protected by trade secret laws. A 2002 study of cosmetics detected phthalates in nearly three-quarters of products tested, despite the absence of any mention of phthalates on any of the products'' labels. The label, if it lists ingredients at all, will often simply state ''fragrance'' without identifying the specific components. Certain phthalates have been shown to cause reproductive and developmental harm in laboratory animals, as well as more acute impacts such as organ damage. Reproductive effects associated with exposure to phthalates include changes in male sexual characteristics, reduced sperm count, and damaged sperm. A May 2005 report showed an association between adverse effects to male children and their mothers'' exposure to phthalates during pregnancy. A study on children with allergic symptoms found a correlation between levels of phthalates in house dust and allergic symptoms and or asthma in children in those homes.
Conclusion and Recommended Actions
Shopping for cleaning products involves personal choices on a number of levels. Which products make your house feel clean? Which products give your clothing the softness or brightness you are looking for? Which products are priced right for your budget and available at your nearest store? Sometimes it comes down to which products you have found to be tried and true for years. This report aims to provide additional information for consumers who may have concerns about their exposure to chemicals in cleaning products. With a growing awareness about the widespread use of toxic chemicals in the consumer marketplace, we are looking for information on how to reduce unnecessary and harmful exposures.
What You Can Do?
1. Use less toxic products. It is not always easy to determine which cleaning products are less toxic. Simply having a ''natural sounding'' brand name does not preclude a product from containing chemicals you may want to avoid. Below are some tips to help you choose less toxic cleaning products.
a. Avoid products marked ''Danger'', ''Poison'', and reduce your use of products marked ''Caution.'' ''Caution'' or ''Warning'' appears on numerous cleaning product labels and indicates a mild hazard from normal exposure, such as skin and eye irritation. ''Danger'' on a label indicates possible permanent damage, and is found on drain and oven cleaners.
b. Reduce your use of products containing Volatile Organic Compounds (VOCs). Reducing the use of products containing VOCs is particularly important if you or someone in your home has asthma. The U.S. EPA''s Indoor Air Quality Program states that the following products types are likely to contain VOCs: aerosol sprays, cleaners and disinfectants, moth repellents and air fresheners.
c. Use fewer products. An all-purpose cleaner can handle a lot of cleaning jobs around the house. It is not necessary to have a different product for each room (bathroom cleaner, kitchen cleaner, etc.)
2. Buy products from manufacturers that disclose ingredients on the label. While labelling for household cleaning products is limited, you can reduce your exposure to chemicals with long-term health effects by purchasing products from manufacturers who list ingredients on their labels. If a product does not include ingredients on the label, call the customer service number on the product and ask the company to disclose the ingredients.
3. Encourage product manufacturers to replace toxic ingredients with safer alternatives. Alternatives do exist for many of the chemicals of concern in cleaning products. If your favourite cleaning product contains a chemical of concern, call the manufacturer and let them know you would prefer they use an alternative chemical.
4. Demand that government require companies to disclose product ingredients and replace toxic chemicals with safer alternatives. Contact your local representative and ask them to support legislation that would require companies to disclose their product ingredients.
This is an edited extract of a report titled ''Household Hazards - Potential Hazards of Home Cleaning Products'' issued by Womens Voices for the Earth July 2007.
by Alexandra Gorman, Director of Science and Research WVE.
The full report can be found on the Science, Health and the Environment Network website; http://www.sehn.org.
