The German Senate Commission for the Investigation of Health Hazards of Chemical Compounds in the Work Area (MAK Commission) re-evaluated the data for devel- opmental toxicity and the derivation of the occupational exposure limit value (maxi- mum concentration at the workplace, MAK value) for 2-methoxyethanol 109-86-4. The MAK value was derived in analogy to the BAT value (biological tolerance value) for the metabolite methoxyacetic acid of 15 mg methoxyacetic acid/g creatinine. This con- centration was extrapolated to a 2-methoxyethanol concentration in air using the find- ings of a volunteer study and toxicokinetic considerations. The MAK value of 1 ml/m3 was retained based on these results. The substance remains classified in Pregnancy Risk Group B because a risk for the developing foetus cannot be ruled out at exposure to the MAK value of 1 ml/m3. This was concluded based on embryo-/foetotoxic and ter- atogenic effects induced by the metabolite methoxyacetic acid in rats, mice, rabbits and monkeys. A 2-methoxyethanol concentration of 0.15 ml/m3 was derived for the work- place from the lowest NOAEC (no observed adverse effect concentration) of 3 ml/m3 for developmental toxicity induced in rabbits by 2-methoxyethanol; damage to the embryo or foetus is unlikely at this concentration (the prerequisite for assignment to Pregnancy Risk Group C).
Hartwig et al. (2025) studied this question.