**4. Symptoms of bee poisoning**


**17**

*Detailed Review on Pesticidal Toxicity to Honey Bees and Its Management*

losses from pesticidal poisoning than weaker ones, because they have larger

• Foraging bees often carry residual pesticides in their pollen loads while returning to the hive. As a result, the behaviour of bees in the hive changes abruptly. Honeybees in such colonies become more aggressive or agitated. When a hive containing pesticide-affected bees is opened, the bees fly out of the hive

• Other symptoms include stupefaction, paralysis, aggressiveness and abnormal behaviour, jerky, spinning movements. Slowing down of activity and crawling of bees around the hive entrance. They lose their ability to fly and ultimately die 2 or 3 days after poisoning. Poor egg laying patterns or abnormal superce-

• Within the hive, a break in the brood cycle (stages of young bees) or a spotty

Classification of different toxicants to honey bees can be done either on the basis of levels of toxicity or on the basis of sources in the nature. Different toxicants have variable toxicity levels, according to their mode of action on bees and this toxicity level is measured as LD50, which is the dose at which 50% of the bee population dies due to the intoxication. On the basis of their LD50 levels, toxicants have been classi-

Second type of classification is based on the type of toxicants which are originated from different sources, due to human interventions. These toxicants include:

The modern time has become an era of the greenhouse gases and global warming. The ever-increasing concentration of various poisonous gasses in the atmosphere has affected a vast majority of the living beings in this world and honey bees are also not any exception with carbon di oxide being the most important of these gasses. Several scientists have worked on the toxicity of carbon dioxide on honey bees and have found some drastic effect of this gas on honey bee at both the levels including individual bees as well as at the colony level, which includes narcosis in foraging honey bees [11], earlier oviposition of queen [20], reduction in life expec-

sometimes straight at the face of the beekeeper handling them.

pattern of the brood could also indicate a pesticide problem.

*DOI: http://dx.doi.org/10.5772/intechopen.91196*

numbers of foraging bees.

dure of queens.

**5. Classification of toxicants**

fied into four different categories [19].

**5.1 Inorganic toxicants**

*5.1.1 Carbon dioxide*

• highly toxic (acute LD50 < 2 μg/bee)

• moderately toxic (acute LD50 2–10.99 μg/bee)

• nontoxic (acute LD50 > 100 μg/bee) to adult bees

tancy [21] and reduction in pollen gathering by foraging bees [1].

• slightly toxic (acute LD50 11–100 μg/bee)

losses from pesticidal poisoning than weaker ones, because they have larger numbers of foraging bees.

