The first group of concerning chemicals are 'very persistent and very bioaccumulative chemicals' - those which persist for a long time and accumulate in the bodies of humans and wildlife (particularly in fat). It is difficult to predict the effects of long-term, low-level exposure to these chemicals. But if they are found to be toxic, as many in the past have turned out to be, we will have to live with their effects for many years to come. Once they are released into the environment it is extremely difficult, if not impossible, to recover them.

The second group are 'endocrine disrupting chemicals' (EDCs). These can mimic, block or interfere with hormones such as oestrogen, androgen and thyroid, affecting wildlife and humans alike. As a result, they can hijack normal biological processes and may cause neurological, behavioural, developmental or sexual defects.

In some instances EDCs are also persistent and bioaccumulative, meaning that mammals can pass them from mother to baby.

Exposure to such chemicals at critical stages in pre- and post-natal development can disrupt the development of hormone-sensitive organs. Adverse effects may only emerge in adulthood, when abnormalities of the reproductive system become apparent.

Inadequate Regulation
The EU has admitted that 99 per cent of the volume of chemicals on the market are inadequately regulated. Of Europe's highest volume chemicals, 21 per cent have no safety data publicly available, and 86 per cent have less data publicly available than the minimum amount required to make even a basic safety assessment.

The current regulations do not recognise that the effects of EDCs can occur at incredibly low doses - measured in parts per trillion! Neither do they take account of the combined effect of several chemicals, or the increased susceptibility of babies and children. In these and many other areas, the existing regulations do not consider the potential impacts of man-made chemicals on humans and wildlife.