In the manufacture of plastics, different substances are added to give it different properties, depending on how and to what it is to be used. For example, if it should be frozen, heated or otherwise used. 

Therefore, to avoid these substances being released and getting rid of them, it is therefore basic rules to only reuse plastic packaging for what they are made for and to keep an eye out for labels.

This is stated by Andreas Berg-Morén, food inspector in Västerås.

- Once a little neighbor may not be the whole world, but it is the "many streams of small principle" throughout our lives we talk about here. In this long-term exposure, every little thing that can be avoided is good.