London: Honeybee populations are shrinking worldwide and a new study says the use of a new generation of pesticides could be blamed for their mysterious decline.
Researchers at the Department of Agriculture`s Bee Research Laboratory in the US found that the new chemicals, which are routinely used on farms and garden centres, attack the insects` central systems and make bee colonies more vulnerable to disease and pests.
The study led by Dr Jeffrey Pettis, one of the US`s top bee experts, found that exposure to a class of pesticides, called neo-nicotinoids, makes bees more susceptible to infection -- even at doses too low to be detected in the creature`s bodies.
Neo-nicotinoids, which were introduced in the 1990s, are applied to seeds and are found in low levels throughout a growing plant -- including in its pollen and nectar.
They were introduced to replace controversial organo phosphates because they appeared to be harmless to mammals and people and are used on oil seed rape, wheat, sugar bed and garden centre plants.
The US research has yet to be published, but is discussed in a new documentary film `The Strange Disappearance of The Bees`, the Daily Mail reported.
Insect charity `Buglife` has said previous studies in France had found a link between pesticides and vanishing bees.
Director Matt Shardlow said: "This American study shows even at levels where you can no longer detect the substance in bees, it is still having an impact on their health.
"People have been wondering what is the cause of the decline of bees and moths and bumblebees in Britain. And the research is further evidence that pesticides are a potential
However, German chemical giant Bayer, which makes many of the neo-nicotinoids used in Europe, insisted its products did not harm bees.
A spokesman of the firm said it was difficult to comment on unpublished studies and that it was impossible to look at the methods used by the researchers.
"I`m sure there are some very interesting effects Dr Pettis has seen in a laboratory, but in reality, when you get to what`s important to everybody which is what happens in the field, you don`t see these things happening.
"Bees are very very important insects to BayerCropScience and we recognise their importance."