Scientists at the Excell laboratories in Bordeaux, France have discovered that only 10 percent of 300 wines tested for contamination with chemicals used in the growing process were free of residues. Up to nine active materials were found in wines tested .

The team, led by Dr Pascal Chatonnet tested wines from 2009 and 2010 vintages grown in three French regions. Fungicides applied late on in the growing season were discovered most frequently.  Wine expert Chatonnet suggested that, although all individual chemicals found were below the required health and safety levels, the presence of several different chemical residues could have a cumulative effect.  

The laboratory has organised a conference to discuss "new perspectives" and means of reducing chemical use in growing in response to its findings.

The wine industry in France uses a proportionately high volume of chemical products on vines, accounting for 20 percent of all agricultural chemicals for products grown on 3 percent of the agricultural area.

The French government has introduced a plan to halve the amount of agricultural chemicals used in the country by 2018. However, farmers have strongly resisted the policy.

Last year, new European laws were introduced to govern the certification of organic wine. However, industry opinion remains divided over whether the rules are comprehensive enough, allowing as they do use of certain chemical inputs.