Survey and release of chemical substances in "slimy" toys

7 Health assessment of two additional products

7.1 Introduction

The Danish Consumer Council has tested 80 pcs. of toy purchased in 10 European countries in collaboration with other European consumer organisations (Forbrugerrådet 2004a). The analysis results have been published on the Internet (Forbrugerrådet 2004b).

As a consequence of the examination, the Danish Environmental Protection Agency decided to have 2 slimy toy products, which were included in the test, analysed and assessed together with the slimy toy products, which were included in the survey project.

7.2 Screening and quantitative analyses

Based on the results of the study of the Danish Consumer Council an analysis of boron is performed by ICP-AES and headspace analysis by GC-MS for VOC, including aliphatic hydrocarbons and styrene. These analyses were performed similar to the analyses of the remaining pieces of slimy toy mentioned in chapter 5. The Danish Environmental Protection Agency has decided not to carry out migration analyses (sweat- and saliva extractions) on the 2 pcs. of slimy toy.

7.3 Identified substances

The substances in the 2 additional slimy toy products have been identified, and the results are presented in Enclosure J and K. The volatile substances detected at headspace (organic substances) are presented below together with the amount of boron detected in a total analysis (inorganic substances).

Table 7.1 Identified volatile substances in the headspace analysis of the 2 products

ID. no.   EX-01 EX-02
Component CAS no. % m/m % m/m
Organic substances      
2-n-Butylacrolein 1070-66-2 4.2  
Cyclohexanone 108-94-1 0.9  
Ethanol 64-17-5   0.1
Heptanal 111-71-7 0.8  
cis-Hept-2-enal 57266-86-1 0.9  
Hexanal 66-25-1 13  
1-Methoxy-2-propanol 107-98-2 7.9  
1-Methoxy-2-propanone 5878-19-3   incl. in 2-propanol
2-Methyl-2-propanol 75-65-0 12  
Nonanal 124-19-6 1.7  
Octanal 124-13-0 1.8  
2-Octene-1-ol 26001-58-1 0.8  
2-Phenoxy ethanol 122-99-6   8.1
1-Propanol 71-23-8 14  
2-Propanol 67-63-0 15 0.3
Propylene glycol 57-55-6   28
Styrene 100-42-5   3.3
Xylenes     2.3
C9H12 aromatic hydrocarbons     17
C10H14 aromatic hydrocarbons     3.2
C9H18 aliphatic hydrocarbons   2.8  
C6 - C7 aliphatic hydrocarbons   26  
C12 - C16 aliphatic hydrocarbons     37

From the above table follows that only one organic substance (2-propanol) is in common. Otherwise, the products have different compositions.

Table 7.2 Quantitative measurements of inorganic substances (mg/kg)

Element CAS no. EX-01 EX-02
    mg/kg mg/kg
Boron 7440-42-8 729 1100
Copper 7440-50-8 2.4 * -
Nickel 7440-02-0 1.0 * -
Selenium 7782-49-2 1.4 * -
Zinc 7440-66-6 13000 * -

* Values from the Danish Consumer Council (2004b)
-: below the limit of detection

7.4 Classification of identified substances

The classification of the identified substances are mentioned in tables below for the volatile organic compounds and the inorganic substances respectively.


Click her to se Table 7.3

Click her to se Table 7.4


Subsequently, the substances have been evaluated based on the chemical substances selected in the other slimy toy products.

7.5 Assessment of 2 additional products

For the sake of comparability the assessments have been carried out in the same way as on the other slimy toy products. In consideration of the readability the used limit values are mentioned again.

Cyclohexanone

Cyclohexanone has previously been detected in 11 out of 20 products. Effect data are presented in section 6.3.4.

Threshold limit values

The threshold limit value is 40 mg/m³ with skin notation (H), i.e. the substance may penetrate the skin (AT 2002).

TCA (tolerable concentration in air): 136 µg/m³ (Baars et al. 2001).

The C-value is 0.1 mg/m³ (C-value guidelines, Miljøstyrelsen 2002).

The oral RfD value is 5 mg/kg bw/day (IRIS 2004).

The TDI value is 4.6 mg/kg/day (Baars et al. 2001).

Assessment

The assessment of inhalation is based on short-term exposure with 1 m³ air in the breathing zone and one hour of exposure, and also a long-term scenario with exposure in 20 m³ room for one hour daily, both for child with 10 kg body weight (bw). The absorption by inhalation has been set at 100%.

Table 7.5 Absorption via inhalation of cyclohexanone

ID no. Lab. no. Content
%
Total,
ng
Breathing zone
concentration
µg/m³
Acute
uptake via
inhalation
µg/kg/day
Chronic
uptake via
inhalation
µg/kg/day
EX-01 31396-19 0.9 10 0.004 0.0005 0.00017

The TDI value of 4.6 mg/kg bw/day was not exceeded. The estimated concentration in the breathing air (1 m³) at acute exposure is 9.2x106 times lower than the TDI value, and the estimated concentration in the air in 20 m³ room (chronic exposure) is 2.7x106 times lower than the TDI value.

Using the NOAEL 462 mg/kg bw/day the margin of safety (MOS) is: 462/0.00000017 = 2.7x108.

Conclusion

Consequently, the release of cyclohexanone is not considered to constitute a health problem.

2-Phenoxyethanol

2-Phenoxyethanol has previously been detected as a volatile substance in 1 product. Effect data are stated in section 6.3.8.

Threshold limit values

The threshold limit value is 110 mg/m³ with skin notation (H), i.e. the substance may penetrate the skin (DF 2001).

The C-value is 0.1 mg/m³ (Miljøstyrelsen 2002).

Assessment

The assessment of inhalation is based on short-term exposure with 1 m³ air in the breathing zone and one hour of exposure, and also a long-term scenario with exposure in 20 m³ room for one hour daily, both for child with 10 kg body weight (bw). The absorption by inhalation has been set at 100%.

Table 7.6 Uptake via inhalation by exposure to 2-phenoxyethanol

ID no. Lab. no. Content,
%
Total,
ng
Breathing
zone
concentration,
µg/m³
Acute
uptake via
inhalation,
µg/kg/day
Chronic
uptake via
inhalation,
µg/kg/day
EX-02 30396-20 8.1 2680 1.152 0.138 0.048

The calculated absorption via inhalation was 138 ng/kg bw/day in the short-term scenario and 48 ng/kg bw/day in the chronic scenario.

Since no TDI value is available, the NOAEL value of 200 mg/kg bw/day has been used. When comparing with this the margin of safety (MOS) for absorption via inhalation was 40×106.

It should be noted that the headspace concentration, which has been measured in 1 litre of air, must be diluted by a factor 1000 to 1 m³, i.e. the concentration in breathing zone is 1.152 µg/m³ air. Thus, this value is approx. 100 times lower than the C-value.

Conclusion

It is assessed not to be a health risk from the exposure of 2-phenoxyethanol.

Styrene

Styrene has previously been detected in 2 products.

Threshold limit values

The threshold limit value for the working environment is 105 mg/m³ with notation LHK. L means that the threshold limit value is a ceiling value, which at no time must be exceeded. H means that the substance can penetrate the skin. K means that the substance is adopted on the list of substances that may be carcinogenic(AT 2002).

WHO has given a 24 hours air quality guideline value of 800 µg/m³ (IPCS 1983) and for continued exposure 260 µg/m³ air (WHO 2000).

The C-value is 0.2 mg/m³ (Miljøstyrelsen 2002).

The RfC value is 1 mg/m³ (IRIS).

The RfD value is 0.2 mg/kg bw/day (IRIS).

TDI is 120 µg/kg bw/day (Baars et al. 2001).

Assessment

The assessment of inhalation is based on short-time exposure with 1 m³ air in the breathing zone and one hour of exposure, and also a long-term scenario with exposure in 20 m³ room for one hour daily, both for child with 10 kg body weight (bw). The absorption by inhalation has been set at 100%.

Table 7.7 Uptake via inhalation by exposure to styrene

ID no. Lab. no. Content,
%
Total,
ng
Breathing zone concentration,
µg/m³
Acute
uptake via inhalation, µg/kg/day
Chronic
uptake via inhalation, µg/kg/day
EX-02 30396-20 3.3 1090 0.467 0.056 0.019

It should be noted that the uptake from this product is 5 times higher than for the previous 2 products, where styrene was detected.

Regarding inhalation the estimated concentration of 0.467 µg/m³ in the breathing zone is below the RfC value of 1 mg/m³ and below WHOs air quality value of 0.8 mg/m³.

Regarding uptake the chronic RfD is 0.2 mg/kg bw/day. The calculated value is a factor 10500 lower. The calculated value is below the stated TDI- value of 0.12 mg/kg bw/day.

Using the NOAEL 12 mg/kg bw/day the margin of safety (MOS) is: 12/0.000019 = 631000.

Conclusion

Based on the calculated scenarios no health problems are expected due to the presence of styrene in the mentioned toy.

Xylene

Xylene was detected as volatile substance in almost all the examined slimy toys.

Threshold limit values

The threshold limit value for working environment is 109 mg/m³ with notation H (can penetrate the skin) (AT 2002).

The C-value is 0.1 mg/m³ (Miljøstyrelsen 2002).

TCA (tolerable concentration in air): 870 µg/m³ (Baars et al. 2001).

The RfC value is 0.1 mg/m³ (IRIS 2004).

TDI (tolerable daily intake): 150 µg/kg bw/day (based on Condie et al. 1988).

The RfD value is 0.2 mg/kg/day (IRIS 2004).

Assessment

The assessment of inhalation is based on short-term exposure with 1 m³ air in the breathing zone and with exposure for one hour, and also a long-term scenario with exposure in 20 m³ room for one hour daily, both for child with 10 kg body weight (bw). The absorption by inhalation has been set at 100%.

Table 7.8 Uptake via inhalation by exposure to xylenes and ethylbenzene

ID no. Lab. no. Content,
%
Total,
Ng
Breathing
zone concentration,
µg/m³
Acute
uptake via
inhalation,
µg/kg/day
Chronic
uptake via inhalation,
µg/kg/day
EX-02 30396-20 2.3 770 0.331 0.0397 0.0137

The concentration in the breathing zone is 0.33 µg/m³, corresponding to 300 times lower than the RfC value.

The uptake via inhalation is below the TDI- value of 150 µg/kg bw/day.

Using the NOAEL 179 mg/kg bw/day the margin of safety (MOS) is: 179/0.0000137 = 1.3x107.

Conclusion

Consequently, xylene and ethylbenzene are not released to an extent that constitute a health problem to the consumer.

Aliphatic hydrocarbons

The aliphatic hydrocarbons may be linear or branched.

The alkanes C6-7 and C12-16 (hexane, heptane and dodecane, tridecane, tetradecane, pentadecane, hexadecane) have been grouped in the measurements.

Effects on health

For many of the aliphatic hydrocarbons dermatitis, irritation, influences on the central nervous system and anaesthesia have been observed. The effects are increased by increased molecular weight. In general, aliphatic mixtures have a neurotoxic effect at approx. 100 ppm corresponding to 200-600 mg/m³ (Larsen et al.1999).

The lowest toxic dose (TDlo) for tetradecane on mice exposed for 20 weeks is 9600 mg/kg according to Clayton and Clayton (1981), who state that C13-C16 alkanes at inhalation have the same effects as C6-C10, but with a slower mortality rate.

Classification

Alkanes, C6-12-branched and linear, are adopted on the List of dangerous substances (Miljøministeriet 2002) with the classification:

Carc2;R45 May cause cancer

Threshold limit values

The threshold limit value for C9-C13: 180 mg/m³ (AT 2002).

LCI for C7-12 is based on a general neurotoxic effect at 200 to 600 mg/m³ in humans, i.e. LCI = NOEL/110 = 20 to 60 mg/m³ is suggested in Larsen et al. (1999).

Other limit values detected for the substances or related substances:

Substance Threshold limit value
mg/m³
LCI,
mg/m³
C-value,
mg/m³
Heptane 820 8  
Octane 930    
Nonane 180 10  
Decane 180 2  
Undecane 180   1
Dodecane 180    
Tridecane 180   1

In the analyses in 1 product (lab no. 31396-20) for the group of C12-16 was detected at a concentration that was recalculated to 5.324 mg/m³ in the headspace container of 1 litre. Diluting this concentration to 1 m³ (the breathing zone), the concentration in the breathing zone is 5.3 µg/m³.

Conclusion

The aliphatic hydrocarbons could not be separated in the chemical analysis and must be considered as a group. Based on the subjective assessment when purchasing the samples the presence of hydrocarbons could be smelled as an oily smell, which is characteristic of hydrocarbons.

The measurements of the evaporated concentrations do not reach the 200 mg/m³, which cause neurotoxic damages according to Larsen et al.(1999). The LCI value of 20 mg/m³ (which is the lowest concentration that can cause irritant effects by inhalation), can only be exceeded by placing the nose very close to the recently purchased product. The data basis is too small in order to give a unambiguous conclusion. However, if the classification is valid for the detected substances, they may be carcinogenic.

Boron

Boron has been detected in 6 of the previously examined slimy toys.

Threshold limit values

The threshold limit value for the working environment is 10 mg B/m³ (ACGIH, boric acid as nuisance dust).

The C-value is administratively set to 0.003 mg B/m³ (Miljøstyrelsen 2002).

The RfD value is 0.2 mg/kg bw/day (IRIS 2004).

The recommended TI (Tolerable Intake) is 0.4 mg/kg bw/day (9.6/25) where it is also recommended that consumer products are allocated 5% of this value = 0.02 mg/kg bw/day (IPCS 1998).

Assessment

Boron was determined as total substance, The results are presented below.

Table 7.9 Content of boron in µg B/g

ID nr. Lab. nr. Weight,
g
Measured content,
µg B/g
Total,
µg
Dermal
uptake
µg/kg/dag
Oral
uptake
µg/kg/dag
EX-01 30396-19 27,9 729 20339 0,4678 20,3
EX-02 30396-20 17,8 1100 19580 0,4503 19,6

The %RSD presents the percentage relative standard deviation made as common estimate based on the relative standard deviation from duplicate determinations.

The highest measured concentration was 1100 µg/g equivalent to 1100 mg/kg or 0.11% of the product.

The estimates of the uptake from the liquid inside the slimy toys are based on the assumption that the liquid may come into contact with the skin or as worst case directly into the mouth. The estimates of the uptake from the exterior parts of slimy toys are based on 1 o/oo migration and 23% uptake via the skin and 100% absorption orally. The uptake via inhalation is estimated to be insignificant from a slimy product.

Thus, the calculations are (example):

dermal uptake: 17.8 × 1100 × 0.23 × 0.001 / 10 = 0.45 µg/kg/day

oral uptake: 17.8 × 1100 × 1.0 × 0.01 / 10 = 19.6 µg/kg/day

Comparing the total uptake of approx. 20 µg/kg bw/day with the chronic RfD value of 0. 2 mg/kg bw/day, no immediate health risks exist.

Using the NOAEL 9.6 mg B/kg bw/day the margin of safety (MOS) is approx.: 9.6/0.020 = 480.

However, it should be remembered that according to Miljøstyrelsen (2004) a proposal to classify boron the same as boric acid. This would result in a classification of at least: Reproduction toxic category 3;R62 and R63, i.e. ”Possible risk of impaired fertility” and ”Possible risk of harm to the unborn child”. Since then the proposed classification is made more rigorous to: Reproduction toxic category 2;R60 and R61, i.e. ”May impair fertility” and ”May cause harm to the unborn child”.

Boric acid is under the EU risk assessment of existing chemical substances but the assessment is not finalised.

Conclusion

Based on the available information it is assessed that the content of boron does not constitute a health problem to the consumer.

7.6 Conclusion

A further 2 products were included in the study. The exposure to most of the volatile substances was assessed not to cause a health risk to the consumer. A rather high concentration of the group of aliphatic hydrocarbons was detected, which are classified carcinogenic.

 



Version 1.0 March 2006, © Danish Environmental Protection Agency