NCBI Bookshelf. A service of the National Library of Medicine, National Institutes of Health.
Meesters JAJ, Nijkamp MM, Schuur AG, et al. Cleaning Products Fact Sheet: Default parameters for estimating consumer exposure: Updated version 2018 [Internet]. Bilthoven (NL): National Institute for Public Health and the Environment; 2018.
Cleaning Products Fact Sheet: Default parameters for estimating consumer exposure: Updated version 2018 [Internet].
Show details7.1. Machine dishwashing detergents
Machine dishwashing detergents are used for cleaning cook ware and table ware (cutlery, crockery, glasses, pans, etc.) (henceforth ‘table ware’) in a dishwasher. The cycling stages of machine dishwashing consist of: a pre-wash cycle, during which food residues are removed by pure water: a wash cycle, when the dishwashing detergent is added; one or two intermittent rinse steps; and a final rinse cycle, in which rinse aid is often added. After that, the cleaned dishes are dried at high temperature (65 ºC). At the end of the dishwashing programme the dishes should be free of residues, rinse aids and detergents (Prud’homme de Lodder et al., 2006a; Falbe, 1987).
A range of liquid, powder and tablet products exists, including dishwashing detergents, glass corrosion inhibitors, rinse aids and salts, as well as pre-treatment products and products to clean or deodorize the dishwashing machine itself (Cleanright, 2016). Rinse aids and salts are necessary for pre-softening of hard water. Multifunctional products combine several of these functions, e.g. 3-in-1 or all-in-one products.
Table 7.1:
General composition of machine dishwashing detergent (www.isditproductveilig.nl; www.cleanright.eu; Prud’homme de Lodder et al., 2006a; Reward Distribution, 2015; Rahman et al., 2013)
| Machine dishwashing detergent | Powder % (w/w) | Tablet % (w/w) | All-in-one % (w/w) | Liquid % (w/w) |
|---|---|---|---|---|
| Surfactants Non-ionic surfactants | 1–5 | <5 | <5 | 5–10 |
| Builders Alkalis Sodium carbonate Sodium silicate Ion exchangers Polycarboxylate Complexing agents Phosphates Phosphonates | 45–70 5–>30 | 0–40 0–15 <5 0–45 <5 | 0–35 0–15 <5 0–70 <5 | 3–10 |
| Bleaching agents Sodium perborate/percarbonate TAED | 5–10 1–2 | 15–40 | 5–15 0–5 | 10–30 |
| Additives
Sodium sulphate Enzymes Dyes Perfume Water | 1 1–3 <1 <1 | 0–10 <1 <1 | 0–40 0–5 <1 <1 | 20–50 <10 <10 30–60 |
Scenarios for consumer exposure
The consumer loads the dishwasher with a powder, liquid or tablet detergent. Filling the machine with powders may generate inhalable aerosols, which may end up on the back of the hand holding the measuring cup. Consequential inhalation and dermal exposure are estimated according to the generic scenario for loading powders (4.1.1).
When using a liquid detergent the consumer removes the cap from the bottle and pours the liquid detergent into the reservoir of the machine. Volatiles may evaporate from the bottle and dermal exposure may occur as splatters end up on the back of the hand. Inhalation and dermal exposure are estimated according to the generic scenario for loading liquids (4.1.2).
No exposure is expected upon loading the dishwasher with a tablet, because that is considered to be a ready-to-use product (4.1.3).
No exposure is expected while the dishwasher is running, because the product is in an enclosed machine during this application phase.
Secondary exposure from ingestion of product residues on the dishes is considered negligible in comparison with hand dishwashing (see Prud’homme et al., 2006a; Falbe, 1987). This form of oral exposure is thus not further described for machine dishwashing.
Frequency
The previous Cleaning Products Fact Sheet (Prud’homme de Lodder et al., 2006a) prescribes a default of 252 times per year, based on data of Weegels (1997). AISE (2002) gives a frequency of 3–7 times per week, with a typical frequency of 5 times. Berkholz et al. (2010) performed a study on consumer dishwashing habits in the UK, which showed that the percentage of owners using the dishwasher at least once a day is 56%. The new default is set at 365 per year in accordance to Berkholz et al. (2010) with a Q-factor of 3, because it is well supported by quantitative data.
7.1.1. Mixing and loading: dishwashing machine powder
To add powder to a dishwashing machine, the consumer first pours powder into a measuring cup and then pours the powder into the machine. In accordance with the generic scenario for loading powder, inhalation exposure is estimated using the inhalation–exposure to spray–instantaneous release model, whereas dermal exposure is estimated using the ConsExpo dermal–direct product contact– constant rate loading model (4.1.1). Defaults for the parameters: room volume, exposure duration, contact rate and release duration are taken from the generic scenario (4.1.1).
Released mass
According to the generic scenario for loading powders (4.1.1), the released mass that is subject to inhalation is 8.3 µg per 200 g of the total product amount used. According to AISE (2014), the amount of dishwashing powder varies between 20 and 46 g per task for regular powders and from 20 to 40 g per task for concentrated powders. The new default for released mass of dishwashing detergent powder is set to 2.5 µg, which is based on the highest value for the amount of powder used (46 g per task). The Q-factor is considered to be 1, because of the conservative approach to the amount used and the assumption that the generic scenario is fit for loading dishwashing powders.
Table 7.2:
Default values for estimating consumer exposure to machine dishwashing powder during mixing and loading
| Default value | Q-factor | Source | |
|---|---|---|---|
| General | |||
| Frequency | 365 per year | 3 | Scenario |
| Inhalation–exposure to spray–instantaneous release | |||
| Exposure duration Released mass Room volume Ventilation rate | 0.25 min 2.5 µg 1 m3 2.5 per hour | 3 1 1 1 | Section 4.1.1 See above Section 4.1.1 Kitchen (Te Biesebeek et al., 2014) |
| Dermal–direct product contact–constant rate loading | |||
| Contact rate Release duration Exposed area | 2.8 mg/min 0.25 min 225 cm2 | 2 3 3 | Section 4.1.1 Section 4.1.1 Back of hand (Te Biesebeek et al., 2014) |
7.1.2. Mixing and loading: dishwashing machine liquid
A consumer removes the cap from the bottle and pours the liquid detergent into the reservoir of the machine. To estimate exposure the ConsExpo inhalation–exposure to vapour–evaporation–constant release area model and the dermal–direct product contact–instant application loading model are used, as described in the generic scenario for loading liquids (4.1.2). Defaults for the parameters: product amount (inhalation), room volume, application duration, exposure duration, product amount (dermal) and mass transfer coefficient are taken from the generic scenario (4.1.2).
Molecular weight matrix
The fraction of water in liquid dishwashing machine detergent ranges between 0.3 and 0.6 (Table 7.1). Following the conservative approach, the default molecular weight matrix is calculated as the molecular weight of water (18 g/mol) divided by the fraction of water in the product (0.3), which yields 60 g/mol. The Q-factor is 2, because the supporting quantitative data are limited.
Table 7.3:
Default values for estimating consumer exposure to dishwashing machine liquid during mixing and loading
| Default value | Q-factor | Source | |
|---|---|---|---|
| General | |||
| Frequency | 365 per year | 3 | Scenario |
| Inhalation–exposure to vapour–evaporation–constant release area | |||
| Exposure duration | 0.75 min | 3 | Section 4.1.2 |
| Product amount | 500 g | 2 | Section 4.1.2 |
| Room volume | 1 m3 | 1 | Section 4.1.2 |
| Ventilation rate | 2.5 per hour | 3 | Kitchen (Te Biesebeek et al., 2014) |
| Release area | 20 cm2 | 2 | Section 4.1.2 |
| Emission duration | 0.3 min | 3 | Section 4.1.2 |
| Application | 20 °C | 4 | Room temperature |
| temperature | 10 m/h | 2 | Section 4.2.2 |
| Mass transfer coefficient | 60 g/mol | 2 | See above |
| Molecular weight matrix | |||
| Dermal–direct product contact–instant application loading | |||
| Exposed area Product amount | 225 cm2 0.01 g | 3 3 | Back of hand (Te Biesebeek et al., 2014) Section 4.1.2 |
7.2. Machine dishwashing rinse aid
Rinse aids reduce the surface tension between the washed dishes and water during the final rinse cycle. Rinse aids allow good drying and prevent glass spots, stains and streaks.
Table 7.4:
General composition of dishwashing machine rinse aids (www.isditproductveilig.nl and www.cleanright.eu)
| Dishwashing machine rinse aids | liquid % |
|---|---|
| Surfactants - Non-ionic surfactants | 5–15 |
| Builders - Citric acid | 0–15 |
| Hydrotopes (solubilizes) | 5–15 |
| Additives Solvents Preservatives Dyes Perfume Water | 5–15 <1 <0.5 <1 50–65 |
Scenarios for consumer exposure
The consumer removes the cap from the bottle and pours the liquid rinse aid into the reservoir of the machine. Volatiles may evaporate from the bottle and dermal exposure may occur as splatters end up on the back of the hand. Such inhalation and dermal exposure are estimated according to the generic scenario for loading liquids (4.1.2). No exposure is expected while the dishwasher is running, because the product is in an enclosed machine during this phase. Oral exposure can occur due to residues left on the washed dishes. According to Weerdesteijn et al. (1999), the residue quantity increases with the detergent concentration and with dishwashing water temperature. The secondary exposure to rinse aid resulting from ingestion of residues on table ware is estimated as described in the respective generic scenario (4.3.4).
Frequency
Based on information of Weegels (1997), the default value for frequency of filling the machine with rinse aid is set at 2 times per 3 weeks, i.e. 35 times per year. The Q-factor is set to 3, because the underlying dataset is neither large nor recent, but was collected specifically for filling a dishwashing machine with rinse aid.
7.2.1. Mixing and loading
To estimate exposure, the ConsExpo inhalation–exposure to vapour evaporation–constant release area model and the dermal–direct product contact–instant application loading model are used (4.1.2). Defaults for the parameters: product amount (inhalation), room volume, application duration, exposure duration, mass transfer coefficient and product amount (dermal) are taken from the generic scenario (4.1.2). The default for the parameter: exposed area is considered equal to that in the scenario for loading liquid dishwashing detergents into a machine (7.1.2).
Molecular weight matrix
The fraction of water in the product ranges between 0.5 and 0.65 (see Table 7.4). Following the conservative approach, the default molecular weight matrix is calculated as the molecular weight of water (18 g/mol) divided by the fraction of water in the product (0.5), which yields
36 g/mol. The Q-factor is 2, because the supporting quantitative data are limited.
Table 7.5:
Default values for estimating consumer exposure to dishwashing machine rinse aid during mixing and loading
| Default value | Q-factor | Source | ||
|---|---|---|---|---|
| General | ||||
| Frequency | 35 per year | 3 | Weegels, 1997 | |
| Inhalation–exposure to vapour–evaporation–constant release area | ||||
| Exposure duration | 0.75 min | 3 | Section 7.1.2 | |
| Product amount | 500 g | 3 | Section 4.1.2 | |
| Room volume | 1 m3 | 1 | Section 4.1.2 | |
| Ventilation rate | 2.5 per hour | 1 | Kitchen (Te Biesebeek et al., 2014) | |
| Release area | 20 cm2 | 2 | Section 4.1.2 | |
| Emission duration | 0.3 min | 3 | Section 4.1.2 | |
| Application temperature | 20 °C | 4 | Room temperature | |
| Mass transfer coefficient | 10 m/h | 2 | Section 4.2.2 | |
| Molecular weight Matrix | 36 g/mol | 2 | See above | |
| Dermal–direct product contact–instant application loading | ||||
| Exposed area | 225 cm2 | 3 | Section 7.1.2 | |
| Product amount | 0.01 g | 3 | Section 4.1.2 | |
7.2.2. Post-application: residues on table ware
A dishwashing machine cleans the dishes in four cleaning phases – rinsing, cleaning with detergents and hot water, rinsing with cold water, rinsing with hot water – plus drying. In total, a dishwashing machine uses about 14 to 20 l water, so that per cleaning phase the machine uses about 4 l water (Consumenten Bond, 2016). Rinse aids are added at the start of phase 4, the rinsing-with-hot-water phase (Miele, 2016). According to the default factory setting, 30 ml of rinse aid is used. The resulting secondary exposure to the rinse aid that ends up on the cleaned dishes is estimated using the oral-direct oral contact–direct oral intake model.
Frequency
The frequency of secondary exposure to rinse aid from oral contact with cleaned table ware is interpreted here as the use frequency of rinse aid: 35 times per year, with a Q-factor of 3 (see above).
Amount ingested
According to the generic scenario (4.3.4), the amount of water left on dishes is 5.5 x 10-5 ml/cm2 and the area of table ware in daily contact with food is 5400 cm2. The concentration of rinse aid is 7.5 g/l, as the scenario describes a use of 30 ml per 4 l (assuming a liquid density of 1 g/ml). This leads to an ingested product amount of 5.5 x10-5 ml/cm2 x 5400 cm2 x 7.5 mg/ml = 2.25 x 10-3 g. The Q-factor is 1, because it is unclear to what extent the rinse aid is washed off after rinsing with hot water.
Table 7.6:
Default values for estimating consumer exposure to dishwashing machine rinse aid from residues on table ware
| Default value | Q-factor | Source | |
|---|---|---|---|
| General | |||
| Frequency | 35 per year | 3 | Weegels, 1997 |
| Oral–direct oral contact–direct oral intake | |||
| Amount ingested | 2.25 mg | 1 | See above |
7.3. Manual dishwashing
Food residues on table ware are removed by washing them in water with dishwashing detergent. Mostly, dirt is removed by a brush, cloth or sponge. A scourer is used for hard-to-remove food residues. The clean items are dried either with a drying-up cloth (tea towel) or by placing them in a drainer to air-dry. The cleaning ability of manual dishwashing products is based on surfactants, solvents and additives (Table 7.7).
Table 7.7:
General composition of liquid hand dishwashing detergents – regular and concentrated products (www.isditproductveilig.nl and cleanright.eu)
| Manual dishwashing detergent ingredient | Regular product % (w/w) | Concentrated product % (w/w) |
|---|---|---|
| Surfactants Anionic surfactants Non-ionic surfactants Amphoteric surfactants | 10–20 0–10 0–3 | 10–30 0–20 0–5 |
| Solvents Alcohol | 0–3 | 0–10 |
| Additives
Preservatives Dyes Hydrotropes Perfume Viscosity-controlling agents Water | 0–1 <0.1 0–1 <0.5 0–0.5 45–80 | 0–1 <0.1 0–0.5 <0.5 0–0.5 45–80 |
Scenarios for consumer exposure
The consumer does not perform a mixing and loading activity with the dishwashing liquid, but directly pours the dishwashing liquid into a sink or a bowl filled with water by squeezing the bottle. Then the consumer manually cleans the table ware with a brush. In the process (‘doing the dishes’), there is dermal contact of hands and forearms with the diluted dishwashing liquid. Inhalation exposure to volatiles also occurs due to substances that evaporate from the dishwashing water. The exposure from doing the dishes is described in the generic scenario for application of diluted products (4.2.3). Secondary exposure is accounted for by considering the ingestion of dishwashing detergent residues on table ware. The generic scenario for ingestion of residues from table ware (4.3.4) is used to estimate such oral exposure.
Frequency
The previous Cleaning Products Fact Sheet (Prud’homme de Lodder et al., 2006a) prescribes a default for hand dishwashing of 426 per year, based on Weegels (1997). AISE (2014) gives a range of 3–21 times a week, with a typical frequency of 14 times a week. Berkholz et al. (2010) performed a study in the UK on consumer habits in hand washing a full set of dishes. The frequency of dishwashing by hand was estimated to be at least once per day for 68–88% of the respondents. Garcia-Hidalgo et al. (2017) present summary data from their survey (n=611), from which it can be derived that over half of the respondents did a dish wash ‘more than once a day’, which is also the answer of the respondent representing the 75th percentile. The frequency data indicate that the previous default is still within range and considered representative today. Therefore, the default is set at 426 per year. The Q-factor is set to 4, because the underlying datasets are large and the data were collected specifically to calclate the frequency of performing manual dishwashing.
7.3.1. Application: manual dishwashing
When doing the dishes, there is dermal contact of hands and forearms with the diluted dishwashing liquid. Inhalation exposure to volatiles occurs due to substances that evaporate from the dishwashing water. The generic scenario for application with diluted products is used to estimate exposure, so that the ConsExpo inhalation–exposure to vapour–evaporation–constant release area model and the dermal– direct product contact–instant application loading model are used (4.2.2). Defaults for the parameters: product amount (inhalation), release area, exposed area and product amount (dermal) are taken from the generic scenario (4.2.3).
Emission duration
Weegels (1997) reports a mean duration of dermal contact with dishwashing water of 11 min (St. Dev=7 min, n=592) and a 75th percentile of 16 min. Andra et al. (2015) present a median duration for hand dishwashing of 15 min, whereas Kalyvas et al. (2014) present a 75th of 12 min. Garcia-Hidalgo et al. (2017) present summary data from their survey (n=611), from which it can be derived that the respondent representing the 75th percentile would report spending between 10 and 30 minutes on a manual dishwashing task. The default of 16 min prescribed in the previous Cleaning Products Fact Sheet (Prud’homme de Lodder et al., 2006a) seems to agree with this quantitative data as a realistic but conservative estimate. The Q-factor is set to 4, because the underlying datasets are large and the data are collected specifically to ascertain the duration of performing manual dishwashing.
Exposure duration
The estimated exposure duration is considered the duration of the dishwashing itself plus the tasks after dishwashing (e.g. emptying the sink or bowl and rinsing the kitchen top with water). This duration is estimated by AISE (2014) to range between 10 and 45 minutes, with a typical duration of 30 minutes. The default is set at 45 min. The Q-factor is 3, because the default may be over-conservative as it is the maximum of a range based on quantitative data.
Application temperature
Initially the temperature of dishwater is high, approximately 60 °C, and it decreases during dishwashing. Ramirez-Martinez et al. (2014) recorded an average water temperature of 36 °C (St. Dev=7.1 ºC), which is lower than the 40–45 °C reported by Falbe (1987). The default value for water temperature is kept at 45 °C, representing a more conservative input. The Q-factor is therefore 3, because the default is the maximum of a relatively narrow range.
Amount of solution used
The amount of solution used refers to the sum of the product amount and the solvent amount. Weegels (1997) derived the 75th percentile for volume of 5 l water in the sink or bowl. The solvent amount here is the 5 l of water that is in the sink or bowl. The product amount refers to the amount of manual dishwashing liquid, which is less than 1% in weight compared with the solvent amount (see below). Therefore, the amount of solution used is set equal to the solvent amount, which is 5 l of water and thus 5000 g. The Q-factor is set to 3, because the data specifically refers to the volume of water in a sink or bowl but the number of samples is limited.
Dilution (times)
The dilution in number times is calculated based on the product amount of 7 g and the 5 l volume of water in which it is diluted (see above). According to AISE (2014), the amount of regular dishwashing liquid used is between 3 and 10 g, whereas the amount of concentrated detergents ranges between 2 and 5 g, both per 5 l of water. Ramirez- Martinez (2014) reported an average value of dishwashing liquid of 5.6 g (St. Dev=5.7 g) per 8 l of water for regular dishwashing detergents. The previous Cleaning Products Fact Sheet (Prud’homme de Lodder et al., 2006a) prescribes a use of 7 g per 5 l water based on the 75th percentile found in the study by Weegels (1997). A concentration of 1.4 g/l reasonably agrees with the data from AISE and Ramirez-Martinez (2014). In order to be consistent, the product amount in the water is thus calculated as 1.4 g/l x 5 l = 7 g. The default dilution in number of times is calculated as (5000 g) / 7 g ≈ 700. The Q-factor is set to 3, because the calculation is based on data that specifically refer to the concentration of dishwasher detergent in the water for manual cleaning.
Product amount – dermal
The volume of water ending up on the exposed skin as a result of dipping the hands and forearms into the water is 22 ml (4.2.3). The concentration of dishwashing liquid in the water is 1.4 g/l. The product amount that is subject to dermal exposure is thus calculated as 1.4 g/l x 22 ml = 31 mg. The Q-factor is set to 3, because the concentration data are of high quality but the supporting data for the volume of water that is in contact with the skin are limited.
Table 7.8:
Default values for estimating consumer exposure to dishwashing liquid during the application phase of manual dishwashing
| Default value | Q-factor | Source | |
|---|---|---|---|
| General | |||
| Frequency | 426 per year | 4 | Garcia-Hidalgo et al., 2017 |
| Inhalation–exposure to vapour–evaporation–constant release area | |||
| Exposure duration | 45 min | 3 | AISE, 2014 |
| Amount of solution used | 5000 g | 3 | Weegels, 1997 |
| Dilution (times) | 700 | 3 | See above |
| Room volume | 15 m3 | 4 | Kitchen (Te Biesebeek et al., 2014) |
| Ventilation rate | 2.5 per hour | 3 | Kitchen (Te Biesebeek et al., 2014) |
| Release area | 1500 cm2 | 3 | Section 4.2.3 |
| Emission duration | 16 min | 4 | Prud’homme de Lodder et al., 2006a |
| Application temperature1 | 45 °C | 3 | Temperature of hot water (Prud’homme de Lodder et al., 2006a) |
| Mass transfer coefficient | 10 m/h | 2 | Section 4.2.2 |
| Molecular weight matrix | 18 g/mol | 4 | Matrix is water |
| Dermal–direct product contact–instant application | |||
| Exposed area Product amount | 2200 cm2 31 mg | 3 3 | Hands + forearms (Te Biesebeek et al., 2014) See above |
1: The vapour pressure of the substance should be adjusted to the application temperature of 40 °C
7.3.2. Post-application: residues on table ware
It is assumed (as worst-case scenario) that all table ware is air-dried and not rinsed with pure water, so that residues on the table ware are proportional to the concentration of dishwasher detergent in the water in which the table ware was manually cleaned. The generic scenario for ingestion of residues from table ware is used to estimate oral exposure. Hence, the ConsExpo oral–direct oral contact–direct oral intake model is used.
Frequency
It is assumed that clean table ware is used every day for food and drinks, which equals a frequency of 365 times per year. The Q-factor is set to 4, because daily exposure is considered obvious in this case.
Amount ingested
According to the generic scenario (4.3.4), the amount of water left on table ware is 5.5 x 10-5 ml/cm2 and the area of table ware in daily contact with food is 5400 cm2. The concentration of the dishwashing detergent in water is 1.4 g/l (see above), which leads to an ingested product amount of 5.5x10-5 ml/cm2 x 5400 cm2 x 1.4 g/l = 0.42 mg. The default remains at 0.42 mg. The Q-factor is 2, because the supporting data are limited.
Table 7.9:
Default values for estimating consumer exposure to manual dishwashing liquid from post-application residues on table ware
| Default value | Q-factor | Source | |
|---|---|---|---|
| General | |||
| Frequency | 365 | 4 | See above |
| Oral–direct oral contact–direct oral intake | |||
| Amount ingested | 0.42 mg | 2 | See above |
- Dishwashing products - Cleaning Products Fact Sheet: Default parameters for esti...Dishwashing products - Cleaning Products Fact Sheet: Default parameters for estimating consumer exposure: Updated version 2018
Your browsing activity is empty.
Activity recording is turned off.
See more...