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Survey and Health Assement of the exposue of 2-year-olds to chemical substances in Consumer Product 1 Introduction1.1 Project backgroundThe continuing increase in asthma and allergy among children and the suspicion that chemical substances may result in serious symptoms such as reduced reproductive ability, premature puberty, and reduced learning ability, have resulted in a desire to reduce childhood exposure to chemical substance in Denmark. In a series of previous projects, the Danish Environmental Protection Agency evaluated the risk associated with individual consumer products. In most cases products do not contain problematic substances in quantities sufficient to constitute a risk in general or isolated use. These projects did not focus on the cumulative effect of a single substance from the many different sources to which one was exposed during a day. Neither has the degree to which certain substances may have harmful effects when in combination with other substances been examined. 2 year-olds are exposed to a huge number of products in their daily life and are thereby exposed to many chemical substances. They are also particularly susceptible because of their physical size (large surface area/small volume). The primary focus is on consumer products, but because the 2 year-old’s exposure to chemical substances is comprised in part of food products and the materials that are in contact with these food products, certain food products and materials and objects that come into contact with these food products have also been examined. Exposure from the indoor climate has also been evaluated based on existing measurements of substances in indoor air and dust. The project will result in an information campaign intended to disseminate the report’s conclusions and provide active advice. The primary target group for the campaign is parents and grandparents who are in daily contact with 2 year-olds, but the project is also expected to have a knock-on effect on Danes in general, raising awareness of their chemical exposure in daily life and generating an understanding that it is possible to reduce unnecessary exposure to chemicals. Background on allergens and endocrine disruptors The project initially focuses on substances that are allergen and/or endocrine disruptive and with which the 2 year-old is in contact in their daily life. For this reason the analyses have focused on both areas, but risk assessment has not been performed for the allergens. In the course of the project, it was decided to focus on the endocrine disruptor in order to limit the scope of the assignment. Allergy Approximately one in five adults in Denmark has contact allergies and at least as many have an allergic respiratory illness.[¹]. The frequency of allergy is increasing. More than 200,000 Danes have experienced allergic contact eczema at some time within the last year. This condition develops through dermal contact with chemical substances in the immediate environment, typically from cosmetic products containing perfumes and preservatives as well as cleaning products and certain types of toys 1. Contact allergy can be prevented if the sufferer is aware of which substances cause the allergic reaction, as the condition only occurs when exposed to sufficient concentrations of chemical allergens in the environment[²]. Endocrine disruptors Endocrine disruptors are, according to the EU’s definition from the Weybridge workshop in 1996, an "exogenous substance that causes harmful effects in an organism or its offspring as a result of changes in the function of the endocrine system." Endocrine disruptors may affect hormone balance in many different ways. They can bind to one of the body’s many hormone receptors, where they can have either an agonistic or antagonistic effect. They can alter the number of hormone receptors and influence cofactors involved in the activation of various receptors. In addition, these substances can alter the synthesis of hormones, change the binding of hormones to proteins and alter the breakdown of hormones (Pharma, 2008). This project focused on anti-androgenic substances and oestrogen-like substances. Anti-androgenic substances are substances that can counteract the production or effects of male sex hormones (androgens), including testosterone. In animal studies, the presence of anti-androgenic substances during the foetal stage may result in nipple retention, reduced anogenital distance, increased occurrence of deformed genitals, incomplete descent of testicles in male offspring, and reduced sperm quality in adult animals. In humans, these substances are thought to play a role in the occurrence of, reduced sperm quality, increased occurrence of congenital deformities in the male sex organs, and increased occurrence of incomplete descent of testicles in young boys. Oestrogen-like substances are substances that can affect the organism in the same way as the female sex hormone, oestrogen. Animal studies have shown that oestrogen-like substances can lead to early development of mammary tissue, early onset of puberty and reduced sperm quality. In humans, these substances are thought to play a role in the development of early onset of puberty and breast cancer. Substances that have been shown to have endocrine disrupting effects in animal studies are typically classified because they have produced serious effects such as cancer, or reproductive damage, in animal studies. In the EU, a candidate list of potential endocrine disruptors is being drawn up that will be prioritised for further studies for their endocrine disrupting effects. As background for this work, lists of endocrine disruptors are being collected from various organisations and countries. These lists have been compared and have resulted in the establishment of a collective EU list of 553 candidate substances for further study of their endocrine disrupting effects. In order to prioritise this effort, the substances have been categorised according to criteria that have resulted in one group of substances for which there is documentation of endocrine disrupting activity in at least one study on a living organism (category 1); one group of substances without sufficient evidence of endocrine disrupting effects, but where there is documentation indicating biological activity related to endocrine disruption (category 2); and substances for which there are no indications of endocrine disrupting properties, or which cannot be evaluated because of insufficient data (categories 3a + 3b). This prioritisation has been carried out in several stages, and all 553 substances as well as a further 33 substances added in the last stage, have now been through the prioritisation process. Subsequently, it is intended to transfer these lists to a dynamic working list, to which substances can be added or deleted as increasing documentation on the endocrine disrupting effects of these substances becomes available. Category 1 includes 194 substances. This does not necessarily mean that there is final proof that the substance is an endocrine disruptor, but there is more or less comprehensive documentation for endocrine disrupting effects in living animals and therefore the substance should be prioritised for closer study of endocrine disrupting properties. Many of the substances in category 1 are already prohibited or partly restricted (this applies to many biocides and pesticides). Some of the substances are subject to an approval process where a risk assessment is performed of the substance’s use in a specific context (such as biocides, medicinal products, etc.). This also applies to the positive lists of cosmetic ingredients, where the Scientific Committee has evaluated the risk at use. A number of substances have also been subjected to closer study in compliance with applicable EU legislation. A detailed description of EU prioritisation work can be found on the EU website, where one can also access the database containing all the substances. http://ec.europa.eu/environment/endocrine/strategy/short_en.htm. The majority of the chemical substances that surround us have however not been tested for endocrine disrupting effects. We therefore do not know with any certainty how many endocrine disruptors we are exposed to in daily life. Endocrine disruptors are thought to be the reason for a [³]:
There is, however, no conclusive proof that the above symptoms can be attributed to endocrine disruptors in our environment. There may be many other causes, such as lifestyle, including changes in diet, smoking habits and alcohol intake. Combination effects Combination effects, also known as cocktail effects, can be defined as effects on a biological system or an organism after exposure to multiple substances at the same time. These substances may originate from the same source or from multiple sources. Combination effects of endocrine disruptors are thought to be a contributing factor in the abovementioned symptoms. New research projects are providing greater knowledge of these combination effects, such as:
"We have a good basis from which to say that there is a connection between exposure to phthalates and conditions such as asthma and allergy. This has been shown in studies from Sweden and Bulgaria, and similar studies are underway here in Denmark. This connection has led researchers to wonder whether there might also be a connection with other conditions such as diabetes, obesity and autism, which like asthma and allergy have increased massively over recent years," says Professor Bjarne Olsen, DTU. Researchers can see a connection between effect of phthalates and respiratory symptoms, asthma and other allergic symptoms, but are not sure of the underlying biological mechanism. Instead of only looking at phthalates, one should perhaps include similar substances, such as bisphenol A, brominated flame retardants, pesticides, etc. There are many open questions, such as why do boys have a four times higher incidence of autism and two times higher incidence of asthma than girls? The cause could be attributed to effects early in life from chemicals that are similar to female sex hormones, explains Carl-Gustaf Bornehag (DTU, 2008). The focus of the project is the 2 year-old’s total exposure to chemical substances in consumer products with which the child is in contact in daily life. In the following, emphasis has therefore been placed on prioritising the potential endocrine disruptors and allergen substances that occur in products that 2 year-olds are in daily contact with, and which also constitute a significant level of exposure. However, no risk assessments have been performed for the allergen substances. In the course of the project, it was decided to focus on potential endocrine disruptors in order to limit the scope of the assignment. 2 year-olds are exposed, like other family members, directly and indirectly, to many products and materials that release chemicals into the indoor climate (both evaporation into indoor air and deposition on dust). These sources include:
These other sources of exposure are included in the risk assessment to the extent that data was available for the selected substances. In addition, 2 year-olds, like the rest of the population, are affected by other factors, such as air pollution (from traffic, wood burning stoves, etc.) that are not covered by the project. 1.2 Project purposeThe focus of the project is the 2 year-old’s total exposure to chemical substances in consumer products with which the child is in contact in daily life. Since 2001, numerous projects have been carried out to assess the risk associated with use of various product groups. These projects have primarily looked at peoples’ exposure to chemical substances from individual products, but the primary aim of the present project is to examine the 2 year-old’s total exposure to chemical substances during 24 hours. The purpose of the project is to:
1.3 The project’s target groupThe project’s target group includes:
The primary target group is parents and grandparents of 2 year-olds, who will be the primary recipients of the information campaign. The campaign works with information aimed directly at the primary target group and has also established a cooperation with organisations, companies, retailers and authorities that can serve as channels for the project’s messages. Institution personnel in nurseries and day-care providers constitute a secondary target group. Apart from encountering the campaign in the media and on the internet (netdoktor.dk), we are also intending to establish cooperation with trade publications that are read by institutional staff. Finally, working with municipal bodies we will disseminate the campaign to institution personnel. 1.4 Report structureThe report’s introduction gives the background for the project as well as the project’s objective and target group. Chapter 3 - "Selected substances and products" explains the inclusion and exclusion of substances and products in the project. In addition, a 2 year-old’s possible exposure to other potential endocrine disrupters, allergens and substances with other harmful health effects. This is done through a literature review, screening analyses of consumer products, and use of (Q)SAR models. Chapter 4 - "Legislation" describes the legislation that refers to the product groups which are studied in the present project as part of the surveying process (Chapter 5 of the report). This involves the statutory order on toys; the statutory order on use of phthalates in toys; the statutory order on cosmetics; regulation of other substances, such as nickel, brominated flame retardants, TRIS, TEPA, PBB, PFOS, arsenic and mercury, regulation of nitroamines, and general rules on limitations on use for certain substance (transferred as of 1 June 2009 to the REACH regulations). Chapter 5 - "Survey" maps out the 12 selected product groups. This entails outdoor clothes in the form of impregnated textile outer clothing (jackets), mittens of the same material as snowsuits, footwear in the form of rubber clogs, footwear in the form of unlined rubber boots, pacifiers, bath soap containers, non-slip figures and bath mats, soft toys, diapers, sunscreen, moisturising cream/oil-based cream/lotion and bed linen. Chapter 6 - "Chemical analyses" - describes the analysis programme, exposure scenarios, results of the screening analyses, quantitative analyses and migration analyses. The results are divided into product groups. Chapter 7 - "Risk assessments" - first presents the methodological considerations for setting up the exposure scenarios, including route of exposure, exposure scenarios (exposure times, etc.). It then discusses the methodical conditions concerning calculation of risk, the most important exposure sources and calculations of exposure via dust and air in the indoor environment. Subsequently, risk assessments of the selected substances are presented. Finally, a cumulative risk assessment of endocrine-like substances is presented. [1] Source: Jeanne Duus Johansen, MD., Centre leader for Videncenter for Allergi [Allergy Knowledge Centre], Gentofte County Hospital [2] Source: Jeanne Duus Jensen, Knowledge Centre for Allergy, Chronic: Allergi overfor kemiske stoffer kan forebygges (Allergy to chemical substances can be prevented) (MiljøDanmark 4/2002), http://glwww.mst.dk/udgiv/12090200.htm [3] Source: University Department for Growth and Reproduction, Copenhagen University Hospital and IndenRigs (newsletter for employees of the Copenhagen University Hospital) [4] Ingeniøren no. 8, 2007 [5] Miljø og sundhed [Environment and Health] supplement no. 7, September 2007 [6] Hass et al. Environmental Health Perspectives Volume 115, Number S-1, December 2007 [7]http://www.videnskab.dk/content/dk/krop_sundhed/hormonforstyrrende_stoffer_
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