In general, the toxicity of individual chemical substances is tested in the laboratory on animals, such as mice, either for oral, dermal, or inhalation toxicity, but the toxicity of mixtures of substances has not yet been described. Studies based on direct exposure of potentially toxic substances to living cells, such as spermatozoa are scarce.
Plastic bags used for semen storage are commonly manufactured with multilayer materials to achieve high gas barrier properties and to avoid oxidation processes during storage. Multilayer materials contain a combination of different plastics, either coextruded or glued with adhesives. Although the individual materials have been well regulated in some fields such as food packaging or pharmaceutical packaging, adhesives are not yet regulated. The general principle of safety and the guarantee that any substance present in the material could endanger consumers' health is also applied to adhesives, but the controls are not as strict as in other materials.
*Dr. Cristina Nerín