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Bees may be getting hooked on nectar laced with nicotine-related chemicals in a similar way to how humans are addicted to the drug in cigarettes. 

Many insecticides contain traces of so-called neonicotinoids, which translates to 'new nicotine-like insecticides'.

And despite not being able to taste them, studies have discovered bees - especially those with parasites - will seek out plants laced with such chemicals.

Researchers offered bees a choice of sipping on pure sugar water or a sugar solution containing low doses of neonicotinoids - nicotine-style chemicals found in pesticides. They found honeybees and bumblebees drank more from pesticide-containing solutions, implying that naturally foraging bees would do likewise

Like nicotine, the neonicotinoids act on certain receptors in the nerve synapses of insects. 

They are more toxic to invertebrates than they are to mammals and birds.

Initially, neonicotinoids were used due to their low-toxicity to many so-called beneficial insects, such as bees. 

However, Europe has placed restrictions on three such pesticides, citing concerns for bees, and debate continues about the impact of low doses on these and other non-target insects.

Supporters of neonicotinoids - made by companies including Bayer and Syngenta - say they have a major benefit because they destroy pests and boost crop yields.

Critics fear they contribute to a decline in bees, which are crucial for crop pollination.

To study these conflicting views, three separate studies have looked at the chemical's affects on the insect. 

Geraldine Wright from Newcastle University and her colleagues offered bees a choice of sipping on pure sugar water or a sugar solution containing very low doses of neonicotinoids.

Professor Wright said she was shocked to find both honeybees and bumblebees drank more from pesticide-containing solutions, implying that naturally foraging bees would do likewise.

'There's a conundrum that they are attracted to the stuff that actually is having a negative impact on their motor function and their ability to collect food and forage,' she explained.

The most likely reason lies in the similarity of the chemicals to nicotine, which itself is produced by tobacco plants to prevent against attacks by insects. 

In large amounts it is toxic, but a little bit acts as a drug.

This was confirmed when researchers from Queen Mary University of London (QMUL) and Royal Holloway, University of London (RHUL), similarly gave bumblebees the option to choose between a sugar solution with nicotine in it and one without. 

Those bees infected with the Crithidia bombi parasite were more likely to go for the nicotine-laced nectar than those that weren't infected.

Infected bumblebees that consumed nicotine delayed the progress of the infection for a few days, showing lower levels of parasites than those that had not. 

However, it did not increase the life expectancy of those bees, meaning that the direct benefits of nicotine for the bee colony remain to be identified.

A separate study gave bumblebees a similar option to choose between a sugar solution with nicotine in it and one without. This research found that bees infected with the Crithidia bombi parasite were more likely to go for the nicotine-laced nectar than those that weren't infected, suggesting the bees could be self-medicating

However, it did not increase the life expectancy of those bees meaning that the direct benefits of nicotine for the bee colony remain to be identified. Consuming nicotine also had negative effects, appearing to suppress the appetite of infected bees much like smoking (stock image) does in humans

Consuming nicotine also had negative effects, appearing to suppress the appetite of infected bees much like smoking does in humans. 

Healthy bees that consumed nicotine also showed shorter lifespans than those that did not consume any. 

Dr David Baracchi from the School of Biological and Chemical Sciences at QMUL, co-author of the research, said: 'While it's clear that there is some benefit to nicotine consumption for parasite-infected bees, a key challenge now is to discover exactly how such natural medication limits the impact of the disease on the bees' society.

'Given the stresses placed on worldwide bee populations by disease, understanding how the bees themselves fight infection is key.' 

Separately, a team of Swedish researchers found that oilseed rape sown from seeds coated in neonicotinoids reduced wild bee density, solitary bee nesting and bumblebee colony growth.

Neonicotinoid exposure did not significantly impact honeybee colonies, possibly because they have larger colonies with more workers and are better equipped to deal with damage, but scientists said the evidence against the chemicals was growing.

'At this point in time it is no longer credible to argue that agricultural use of neonicotinoids does not harm wild bees,' said David Goulson, a biologist at the University of Sussex, who was not involved in either of the research efforts.

The bee studies were published in the journal Nature.