Technical Report 126

Chemicals in Other Consumer Products

This section considers chemical exposure from the use of consumer products other than personal care and cosmetic products, household products and foods. These products containing chemicals are used in a large variety of applications. The statutory definition of a consumer product is much broader than just traditional personal care and household cleaning products. It includes all products used in homes, such as surface coatings, adhesives, sealants, disinfectants, automotive care products, toys etc. The landscaping exercise indicated that tools and data are available to support individual product evaluations, particularly at a screening level. For higher tier individual product assessments modelling tools are available, but the level of data for refining the assessment, particularly for parameters that may be considered business confidential such as weight fraction, may be limited.

To our knowledge, limited work has been done on the development of aggregate exposure assessment methodologies and data sources for chemical substances used in consumer products and articles other than cosmetics, food and household care. Most effort in recent years has been dedicated towards development of exposure assessment tools and data that could be used as input for a large amount of chemical risk assessments performed for REACH. These tools (e.g. ECETOC TRA, ConsExpo) and data sources (e.g. RIVM factsheets) generally have two important features: they need to be able to cover a large amount of different chemicals and uses and need to be conservative (reasonable worst case) to ensure the assessments can be performed at a relatively generic level and still provide safe use conditions for the product or contributing activity of use under consideration. The tools generally allow summation of exposure or risk over different exposure routes (oral, dermal and inhalation) within a defined use. None of the main models and tools developed included the ability to assess exposure aggregation over different uses or product categories. The purpose of screening level tools such as TRA is to intentionally develop high end estimates of exposure (low tier assessments), so that if this high end exposure is safe all lower exposures would also be safe. High end exposures are not appropriate for addition because adding up exposures from individual high end scenarios effectively compounds conservatism, quickly resulting in unrealistically high exposure estimates. These values can be too far departed from reality to provide useful information. Tools designed to assess individual scenarios do not contain information on product co-use patterns or data on the market share for specific ingredients, as even within a single product type, the ingredient concentration and presence will vary).

Aggregate exposure assessment for chemicals in consumer products is complex for a number of reasons, including: 1) the consumer product category includes a wide range of substances/products and uses that are in many cases not clearly associated (e.g. fuel and Do-It-Yourself (DIY) products), and co-use patterns have not been identified; 2) a number of product categories like DIY products (coatings, glues) will generally have a very low use frequency, and 3) minimal information is available on formulation of commercial products, making it challenging to estimate how often a consumer may use products that contain a chemical of interest.

Table 1 provides an example of a mapping performed for a REACH chemical safety assessment of all the products and uses for a single chemical substance. The overview illustrates the variety and range of uses many of which occur simultaneously very infrequently. This said, for other product categories this may not necessarily be the case and more information on the likelihood of co-use and thus need for aggregate exposure assessment may be appropriate.

Table 1: Example of a mapping of generic consumer exposure scenarios (GES) and associated uses for a generically used solvent as part of the chemical safety assessment (Source: CEFIC/ESIG GES, v.2012)

Generic exposure scenario Description of generic exposure scenario Description of individual consumer uses included in GES
Uses in coating Covers the use in coatings (paints, inks, adhesives, etc.) including exposures during use (including product transfer and preparation, application by brush, spray by hand or similar methods) and equipment cleaning Use as:

Adhesives, sealants

Anti-freeze and de-icing products

Biocidal products (e.g. disinfectants, pest control)

Coatings and paints, thinners, paint removes

Fillers, putties, plasters, modelling clay

Finger paints

Non-metal-surface treatment products

Ink and toners

Leather tanning, dye, finishing, impregnation and care products

Lubricants, greases, release products

Polishes and wax blends

Textile dyes, finishing and impregnating products; including bleaches and other processing aid

Use in cleaning agents Covers general exposures to consumers arising from the use of household products sold as washing and cleaning products, aerosols, coatings, de-icers, lubricants and air care products Air care products

Anti-freeze and de-icing products

Biocidal products (e.g. disinfectants, pest control)

Coatings and paints, thinners, paint removes

Fillers, putties, plasters, modelling clay

Finger paints

Lubricants, greases, release products

Washing and cleaning products (including solvent based products)

Welding and soldering products (with flux coatings or flux cores.), flux products

Lubricants Covers the consumer use of formulated lubricants in closed and open systems including transfer operations, application, operation of engines and similar articles, equipment maintenance and disposal of waste oil Adhesives, sealants

Lubricants, greases, release products

Polishes and wax blends

Use in agrochemicals Covers the consumer use in agrochemicals in liquid and solid forms. Fertilisers

Plant protection products

Use as a fuel Covers Consumer Uses in Liquid Fuels Fuels
Functional fluid Use of sealed items containing functional fluids e.g. transfer oils, hydraulic fluids, refrigerants Heat transfer fluids

Hydraulic fluids

De-icing and anti-icing applications De-icing of vehicles and similar equipment by spraying Anti-freeze and de-icing products
Other consumers uses Covers the use of the substance for the treatment of water in open and closed systems Perfumes, fragrances

Cosmetics, personal care products

Water treatment chemicals Water softeners

Water treatment chemicals

It is clear from the landscaping overview included in this report that for some product categories, like household products, steps have been taken to build relevant databases to better inform exposure assessment. Also in the personal care and cosmetics categories there have been large advances in available data sets (COLIPA exposure studies) and models (CONSEXPO, PACEM and Creme Care & Cosmetics) over the last decade. For other product categories, this is less clear but recent initiatives like SCED’s (Specific Consumer Exposure Determinants), will lead to more representative data on use characteristics, and therefore, a more refined exposure assessment. This may in the end also enable assessors to look at aggregation of exposures over different uses.

Some of these key developments are discussed below, with consideration to what extent the available data and tools from other areas can provide information that could be used for chemical products. In addition, insight is provided on key data that needs to be generated to better estimate aggregate exposure. This will be further illustrated by several examples from both chemical products and cosmetics and food.

Current chemical exposure assessment approaches

In the EU, the exposure assessment of chemicals in consumer products is currently primarily driven by the obligations for REACH to provide chemical safety assessments for all substances and substance use in products in the European Union. A useful approach in the development of tools and data has been the assessment of generic exposure scenarios (e.g. covering many specific uses as shown in Table 1) for producing conservative estimates to assure safe use across these generic exposure scenarios. Since it was necessary to assess a large number of chemicals within a relatively short time frame, most assessments were performed using generic conservative tools. Inputs were generally conservative default parameters characterising the Generic Exposure Scenarios (GES). These parameters were defined based on knowledge from producers and downstream users on what would be reasonable worst case situations. An example of this is the extensive development of GES for solvents lead by the solvent trade organisation and several large companies. The solvent GES basically include a complete mapping of all relevant uses and products (both consumer and worker) and they were used to generate exposure assessments with tools like ECETOC TRA. Some of the modelling tools enable the user to conduct a more realistic consumer exposure assessment (e.g. EGRET, ConsExpo) based on the refined default input parameters.

For the assessment of consumer exposure as described above the assessor at least needs information on; 1) the substance properties, 2) the relevant consumer exposure scenarios, 3) conditions of use: general environmental and activity characteristics and risk control measures. This information can be used in one of the standard exposure assessment tools (e.g. ECETOC TRA or EGRET for solvents) to generate exposure estimates for each use and each exposure route.

It is the responsibility of individual companies to ensure the exposure scenarios defined in the chemical safety assessment are actually in line with actual work practices. This is in many cases communicated via the labels on the products and/or accompanying use instructions for consumers.

Current developments

Several activities were identified to improve the information available on consumer use of chemical substances. The scope of these activities is generally to improve the quality of the available data making them more representative and underpin assumed default values. As mentioned some of these activities may generate data that will also enable or facilitate to some extend aggregate exposure assessments. Below we describe some of the key activities, data sources and models that are being developed.

SCED’s

The Specific Consumer Exposure Determinants or SCEDs aim to enable exposure assessors to generate more representative exposure estimates (DUCC/CONCAWE, 2014). SCEDs are being developed by several sector organisations to transparently document the way consumer products are commonly used. The SCEDs document typical conditions of use of consumer products. This information is presented in such a format that can be directly used in commonly applied exposure assessment tools. The data provided by the SCEDs is intended to represent realistic assumptions for consumer exposure scenarios and thus lead to (more) realistic and representative assessments of consumer exposure. SCEDs focus on determinants related to consumer habits and practices (e.g. quantity of product used, frequency of use, place of use, etc.). Although not initiated with aggregate exposure in mind and also not including specific parameters that may be needed for aggregate exposure assessment like co-use, the SCEDs should result in a decrease of the level of conservatism which currently is one of the major obstructions for moving to aggregate exposure assessment.

Each determinant described in the SCEDs needs a reference to information sources that was/were used to define it. The data sources should preferably be open access (published) and peer reviewed. The data should as much as possible be representative to European users. The SCEDs are designed so that the resulting exposure scenario as a whole represents conservative, yet realistic exposure situations. Each individual determinant within a SCED is not necessarily a worst case value. Where habits and practices significantly vary across European countries/regions, then the SCEDs will reflect those areas with the highest uses/exposure conditions.

The SCEDs address use conditions relevant for systemic repeated long term exposure – i.e. they must be reviewed to confirm their relevance for local or acute end points (for example, frequency of use would not be an appropriate factor to modify for an acute assessment):

  • They cover the direct uses of consumer products or articles. SCEDs specific to children will only be developed in cases where consumer products are actively marketed for use by children.
  • They do not cover accidental exposures.
  • They describe the use of a product. It is not substance specific; nevertheless, some limitations may apply depending on the substance properties (for example, handling/containment practices may vary depending upon volatility, such as the case for LPG vs. diesel fuels).

Consumer exposure factsheets

The RIVM General Factsheet has been updated in 2014 (te Biesebeek et al, 2014). The current version retains the defaults for room size (20 m3) and indoor ventilation (0.6 h-1) having included and analysed new available data. The default values for body weight, inhalation rate and exposed skin surface areas have been updated. In addition, the factsheet presents information on the ventilation in houses and includes a new chapter on time activity patterns (i.e. how people spend their time).

In 2015 RIVM initiated the review and update process of their cleaning products fact sheet (Prud’homme de Lodder et al, 2006). After the data compilation phase the new information sourced from large-scale consumer products use studies like EPHECT (Dimitroulopoulou, 2015a,b) will be analysed and compiled into the updated factsheet.

Models

The modelling tools, aimed at understanding aggregate exposure from non-occupational sources, e.g. use of consumer products or due to environmental contamination, are currently being developed. The INTEGRA (Integrated External and Internal Exposure Modelling Platform) computational platform is based on the existing platform developed in the frame of the CEFIC-LRI B4 INTERA and B5 TAGS projects. Merlin (Modelling Exposure to chemicals for Risk assessment: a comprehensive Library of multimedia and PBPK models for Integration, Prediction, uNcertainty and Sensitivity analysis Expo tool[1] that is based on a library of models simulating the fate of chemicals (organic substances and metals) in the main environmental systems and in the human body.

Use of a maximum aggregate ratio approach in aggregate exposure assessment

Exposure modelling tools developed for REACH are generally overly/unrealistically conservative and hence, inappropriate for aggregate exposure assessment. For example, a quick reality check with the consumer ECETOC TRA for only painting products (assuming daily use by EU population and TRA defaults) resulted in an excessive annual production volume of the substance of over 8 trillion tonnes (Zaleski, 2011). Thus, while being useful to determine safety, lower tier tools may not provide a realistic estimate of general population exposure that could be summed up with other exposures to obtain realistic assessments of aggregate exposure. Similar issues are encountered when using the SCCS notes of guidance to determine consumer exposure to preservatives in personal care products and cosmetics, and methods of refining these estimates are presented in the triclosan and phenoxyethanol case studies later in this document.

Before carrying out an aggregate exposure assessment, it should be addressed whether there is in fact benefit or value in doing so. Little insight may be gained if it is a single source or use driving the exposure and other contributions are marginal. In addressing the somewhat parallel issue in cumulative exposure, the question is often asked whether a single chemical is driving risk or whether the risk is truly as a result of multiple chemicals in a mixture. One technique used to address this question in cumulative risk assessment is the Maximum Cumulative Ratio (MCR) developed by Price and Han (2011). In short, the purpose of this approach is to help determine if one or few of the multiple substances being assessed contribute to overall risk. The MCR is the total risk potential divided by the maximum risk value associated with a single component. An MCR value closer to one suggests that one or few constituents contribute significantly to overall risk, whereas an MCR closer to N (with N representing the number of constituents included in the assessment) suggests that the contribution of multiple constituents may be useful to consider. This concept can be applied to screening level results to determine if the extra effort of assessing all constituents should be done as a first prioritisation, or if a more focused effort on those contributing greatest to the estimates risk may be more pragmatic. An adaptation of such a technique may also be of use in aggregate exposure assessment when determining whether a detailed aggregate exposure will provide benefit. It is suggested to use an MAR or maximum aggregate ratio representing the total exposure from all sources divided by the maximum exposure from a single source. MAR, might be useful for understanding if overall exposure may be dominated by few or many sources, and to focus any further efforts on those of more importance. It is noteworthy that the MCR concept is to be applied to toxicity estimates derived from dose additive models. The additivity principle will also apply to aggregate exposure provided that single product exposures are aggregated/summed on an appropriate time scale that respected the chemical elimination kinetics. When developing an aggregate exposure estimate, a first step could be to screen the individual exposure scenarios for use information and divide the products into different groups according to their use frequency, duration and amount of use.

To investigate the usefulness of such an approach to a screening aggregate consumer exposure assessment we calculated consumer exposure to a hypothetical highly volatile solvent (VP>10 Pa at ambient temperature) using the EGRET model. The model embeds realistic estimates for exposure determinants derived from consumer use surveys and databases. The exposure predictions are thus representative of reasonable worst-case scenarios. The REACH use descriptor product categories (PCs) that are relevant for the solvent use were then allocated to individual groups based on their use frequency. The most frequently used product group included PCs that are used more than once a week. The next group embraced those PCs that are used more than monthly. The products that are used less than monthly and less than yearly, respectively, constituted the last two groups. The single PCs exposures as well as the resulted aggregate (i.e. summed) exposure across different product groups are provided in Table 2.

Table 2: Reasonable worst-case consumer exposure to a highly volatile solvent assessed using the EGRET v.1.0 model. Product categories highlighted in grey were excluded from aggregate exposure assessment

Descriptor Product subcategory Product Group Frequency, 1/day Duration, h/day Predicted Dermal Exposure, Daily (mg/kg/d) Predicted Oral Exposure, Daily (mg/kg/d) Predicted Inhalation Exposure, Daily (mg/kg/d) Total Daily Exposure, mg/kg/day Products Contributions and MAR Total Chronic exposure, mg/kg/day MULTIPLIED by USE FREQUENCY Product contributions and MAR
PC3:Air care products Air care, instant action (aerosol sprays) Group 1: Products used not less than weekly 4 1 0 0 0.05 0.05 0.0% 0.21 0.1%
PC1:Adhesives, sealants Glues, hobby use 1 4 1.8 0 4.7 6.5 0.1% 6.5 3.5%
PC1:Adhesives, sealants Sealants 1 1 1.8 0 19.3 21.1 0.3% 21.1 11.3%
PC3:Air care products Air care, continuous action (solid and liquid) 1 8 0.0001 0 0.09 0.09 0.0% 0.09 0.0%
PC4_n:Anti-freeze and de-icing products Washing car window 1 0.017 0 0 0.00 0.0001 0.0% 0.0001 0.0%
PC4_n:Anti-freeze and de-icing products Pouring into radiator 1 0.17 7.1 0 1.01 8.14 0.1% 8.1 4.4%
PC4_n:Anti-freeze and de-icing products Lock de-icer 1 0.25 17.9 0 0.28 18.1 0.3% 18.1 9.7%
PC8_n: Biocidal products (excipient use only for solvent products) Laundry and dish washing products 1 0.5 0.07 0 0.37 0.44 0.0% 0.44 0.2%
PC13:Fuels Liquid (subcategories added): Home space heater fuel 1 0.03 35.0 0 0.13 35.1 0.6% 35.1 18.8%
PC18_n: Ink and toners Inks and toners. 1 2.2 1.2 0 5.6 6.8 0.1% 6.8 3.6%
PC34_n: Textile dyes, finishing and impregnating products   1 1 0.14 0 9.9 10.0 0.2% 10.0 5.4%
PC35:Washing and cleaning products (including solvent based products) Laundry and dish washing products 1 0.5 0.07 0 0.37 0.44 0.0% 0.44 0.2%
PC8_n: Biocidal products (excipient use only for solvent products) Cleaners, liquids (all purpose cleaners, sanitary products, floor cleaners, glass cleaners, carpet cleaners, metal cleaners) 0.35 0.12 7.1 0 0.46 7.6 0.1% 2.7 1.4%
PC8_n: Biocidal products (excipient use only for solvent products) Cleaners, trigger sprays (all purpose cleaners, sanitary products, glass cleaners) 0.35 0.06 10.7 0 0.97 11.7 0.2% 4.1 2.2%
PC35:Washing and cleaning products (including solvent based products) Cleaners, liquids (all purpose cleaners, sanitary products, floor cleaners, glass cleaners, carpet cleaners, metal cleaners ) 0.35 0.12 7.1 0 0.46 7.6 0.1% 2.7 1.4%
PC35:Washing and cleaning products (including solvent based products) Cleaners, trigger sprays (all purpose cleaners, sanitary products, glass cleaners) 0.35 0.06 10.7 0 0.97 11.7 0.2% 4.1 2.2%
PC13:Fuels Liquid - subcategories added: Automotive Refuelling Group 2: Products used not less than monthly 0.14 0.007 35.0 0 0.84 35.8 0.6% 5.1 2.7%
PC13:Fuels Liquid - subcategories added: Scooter Refuelling 0.14 0.005 35.0 0 0.56 35.6 0.6% 5.1 2.7%
PC13:Fuels Liquid - subcategories added: Lamp oil 0.14 0.002 35.0 0 0.07 35.1 0.6% 5.0 2.7%
PC23_n: Leather tanning, dye, finishing, impregnation and care products Polishes, wax / cream (floor, furniture, shoes) 0.08 0.1 35.8 0 27.8 63.6 1.0% 5.1 2.7%
PC31:Polishes and wax blends Polishes, wax / cream (floor, furniture, shoes) 0.08 0.1 35.8 0 70.5 106 1.7% 8.5 4.5%
PC13:Fuels Liquid - subcategories added: Garden Equipment - Use 0.07 0.14 0 0 4.0 4.0 0.1% 0.28 0.1%
PC13:Fuels Liquid (subcategories added): Garden Equipment - Refuelling 0.07 0.002 70.0 0 0.44 70.4 1.1% 4.9 2.6%
PC9b:Fillers, putties, plasters, modelling clay Fillers and putty Group 3: Products used several times per year 0.033 0.13 0.12 0 2.9 3.1 0.0% 0.10 0.1%
PC9b:Fillers, putties, plasters, modelling clay Plasters and floor equalisers 0.033 0.07 2.9 0 367 370 5.9% 12.2 6.5%
PC23_n: Leather tanning, dye, finishing, impregnation and care products Polishes, spray (furniture, shoes) 0.022 0.0079 35.8 0 9.6 45.4 0.7% 1.00 0.5%
PC31:Polishes and wax blends Polishes, spray (furniture, shoes) 0.022 0.007 35.8 0 6.0 41.8 0.7% 0.92 0.5%
PC1:Adhesives, sealants Glue from spray 0.016 0.07 1.8 0 44.1 45.9 0.7% 0.76 0.4%
PC24: Lubricants, greases, and release products Sprays 0.016 0.003 35.7 0 6.7 42.5 0.7% 0.70 0.4%
PC9a:Coatings, paints, thinners, paint removers Solvent rich, high solid, water borne paint 0.016 0.04 19.7 0 285 305 4.9% 4.9 2.6%
PC15_n: Non-metal surface treatment products Solvent rich, high solid, water borne paint 0.016 0.04 19.7 0 285 305 4.9% 4.9 2.6%
PC9a:Coatings, paints, thinners, paint removers Waterborne latex wall paint 0.011 0.02 1.1 0 57.7 58.8 0.9% 0.65 0.3%
PC15_n: Non-metal surface treatment products Waterborne latex wall paint 0.011 0.02 1.1 0 57.7 58.8 0.9% 0.65 0.3%
PC16_n: Heat transfer fluids Liquids 0.011 0.002 78.0 0 2.2 80.2 1.3% 0.88 0.5%
PC17_n: Hydraulic fluids Liquids 0.011 0.002 78.0 0 2.2 80.2 1.3% 0.88 0.5%
PC24: Lubricants, greases, and release products Liquids 0.011 0.002 78.0 0 2.2 80.2 1.3% 0.88 0.5%
PC9a:Coatings, paints, thinners, paint removers Removers (paint-, glue-, wall paper-, sealant-remover) 0.008 0.02 71.5 0 326 398 6.4% 3.3 1.7%
PC15_n: Non-metal surface treatment products Removers (paint-, glue-, wall paper-, sealant-remover) 0.008 0.02 71.5 0 326 398 6.4% 3.3 1.7%
PC9a:Coatings, paints, thinners, paint removers Aerosol spray can Group 4: Products used less than yearly 0.005 0.002 0 0 18.8 18.8 0.3% 0.09 0.1%
PC15_n: Non-metal surface treatment products Aerosol spray can 0.005 0.002 0 0 18.8 18.8 0.3% 0.09 0.1%
PC1:Adhesives, sealants Glues DIY-use (carpet glue, tile glue, wood parquet glue) 0.003 0.02 5.5 0 3548 3553 57.1% 9.59 5.1%
Aggregate exposure for Group 1 (N of PCs = 16): 126 3.6 114 3.2
Aggregate exposure for Groups 2-4 (N of PCs = 25): 6,101 1.7 73 6.0
Aggregate exposure ALL (N of PCs = 41): 6,227 1.8 187 5.3
         

The example in Table 2 demonstrates that introducing the annual use frequency into aggregate exposure calculations by means of product grouping can result in a significant reduction of the estimated exposure. For example, aggregate acute exposure, on a day of use, for frequently used products only (i.e. Group 1) was 50 times lower than the aggregate exposure from all the PCs identified for that solvent use. In the case of long term exposure, the reduction was less prominent, i.e. 60%, however it may still impact the outcomes of the follow-up health risk assessment. An exposure assessor may also consider carrying out a feasibility check and calculate the total duration of aggregate exposure. In this example the total time needed to perform only frequent tasks (i.e. application of PCs in Group 1) would amount to 19 h suggesting that all exposure events are unlikely to occur on the same day. Given the conservative nature of the tool, it is important to understand that addition of the individual estimates would only be used to indicate safety; additive exposures greater than a benchmark value indicate that further refinement of the exposure assessment is needed.

Contributions of individual PCs into aggregate exposure varied depending on exposure route and the type of exposure (i.e. acute versus chronic). On the day of use only few products (e.g. DIY glues, paints and coating removers) contributed significantly to the total aggregate exposure from all PCs. MARs were closer to 1 rather than to N (where N = number of PCs in the assessment), showing that the aggregate exposure was dominated by few PCs. In the case of chronic exposure when the annual use frequency parameter came into play the situation changed – more frequently used products in Group 1 outweighed the contributions from occasionally used PCs (Groups 2-4). Increase in MARs for infrequent and all PCs indicates that higher exposure infrequent events are less frequent leading to a more even profile of contributions across the scenarios.

It is worth mentioning that the total exposure over routes was calculated assuming identical health endpoints that are independent of the route of entry into the human body. If this assumption cannot be proven, the total exposure, PCs contributions and MARs should be calculated on the basis of Risk Characterisation Ratio (RCR) that are the ratios of estimated exposure to derived no observed effect levels for the substance of interest. The MAR approach is seen as a complementary tool for screening aggregate exposure assessment that can help to identify whether higher tier assessment is indeed needed. It can also highlight application scenarios requiring further refinement.

The described approach enables identification of product groups with different potential relevance for aggregate exposure assessment. The information generally available is not real co-use data but rather reasonable worst case information on use frequency and use duration. The exposure assessor should always use expert judgement to determine if the data available makes sense or really is only generated to create a worst case but not very realistic exposure scenario. If the data is reasonable it could be used for a first decision on the potential need for an aggregate exposure assessment and in addition used to screen for uses and products to include in a first tier aggregate exposure assessment. An initial focus may be on products that are likely to be used daily, and constituents that are assumed to have large market share in those products. These considerations may help to direct additional efforts to refine defaults and better represent population variability, the types of data needed to conduct a meaningful aggregate assessment. However, other considerations may also apply, such as chemical half-lives, relative toxicity, route-specific effects. A total aggregate assessment would then sum exposure estimates over all types of sources including, but not necessarily limited to, household products, food and cosmetics.

 

[1] Available at http://merlin-expo.eu/