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Popular organochlorine pesticides like DDT (dichlorodiphenyltrichloroethane)
have been replaced by moderately toxic broad-spectrum insecticides, including
organophosphates and carbamates and synthetic pyrethroids. Unfortunately, exposures to the organophosphates and carbamates still pose major threats to the different avian species. Having being important component of the ecosystem and their
plentitude and sensitivity to direct and indirect effects of environment birds make
themselves best indicators of early warning of any environmental problems and
threats. Species of different shore, grassland, farmland, and migratory birds are
directly exposed to lethal doses of these pesticides or through secondary poisoning.
Both organophosphates and carbamates are anti-cholinesterase chemicals, and
intoxication emanates through the inhibition of acetyl cholinesterase, resulting in an
accumulation of acetylcholine at synaptic junction following subsequent activation
of cholinergic receptors which leads to respiratory damage and eventual death.
Avian exposure to these pesticides occurs through dermal contact, inhalation, and
predominantly the ingestion of contaminated foods such as seeds or insects. A number of factors intensify the likelihood of exposure of birds to pesticides such as
cultivation practices, pest types, crop types, pesticide form, diet, and habitat preferences. The sublethal effects of organophosphates and carbamates on birds are manifolds, including malformed embryos, smaller broods, decreased parental diligence,
reduced territorial defence, anorexia and weight loss, subdued immune response,
lethargic behaviour, greater susceptibility to predation, interference in thermoregulation, endocrine disruption, and inefficiency to orient in the proper direction for
migration. Thus, pesticide intoxication reduces the chance of survival and successful reproduction that ultimately perturb to flourish a healthy bird population. The
present review tries to encompass the up-to-date information on the succession of
the anthropogenic use of pesticide and their consequences on selected bird populations, emphasizing organophosphates and carbamates in particular.
Keywords Birds · Organophosphate · Carbamate · Lethal effect · Sublethal effect
3.1 Introduction
The human population of the world is predicted to increase approximately 10 billion
by 2050 (Saravi and Shokrzadeh 2011). With the greater demand for food, intensification of agriculture becomes the primary objective for researchers and implementers. To produce more in the finite land mass, soil amendments (like use of fertilizers)
and application of pesticides (for crop protection, as a whole) are common (Köhler
and Triebskorn 2013; Gill and Garg 2014). Pesticides become indispensable in agriculture and are used for different purposes like crop protection, stored grain, floral
gardens, and eradication of the pests transmitting infectious diseases in plants. Each
year throughout the world, nearly 38 billion USD is spent (12.5 billion USD for the
USA alone) on synthetic pesticides (US EPA 2011; Germany 2012).
A. Mitra et al.
Popular organochlorine pesticides like DDT (dichlorodiphenyltrichloroethane)
have been replaced by moderately toxic broad-spectrum insecticides, including
organophosphates and carbamates and synthetic pyrethroids. Unfortunately, exposures to the organophosphates and carbamates still pose major threats to the different avian species. Having being important component of the ecosystem and their
plentitude and sensitivity to direct and indirect effects of environment birds make
themselves best indicators of early warning of any environmental problems and
threats. Species of different shore, grassland, farmland, and migratory birds are
directly exposed to lethal doses of these pesticides or through secondary poisoning.
Both organophosphates and carbamates are anti-cholinesterase chemicals, and
intoxication emanates through the inhibition of acetyl cholinesterase, resulting in an
accumulation of acetylcholine at synaptic junction following subsequent activation
of cholinergic receptors which leads to respiratory damage and eventual death.
Avian exposure to these pesticides occurs through dermal contact, inhalation, and
predominantly the ingestion of contaminated foods such as seeds or insects. A number of factors intensify the likelihood of exposure of birds to pesticides such as
cultivation practices, pest types, crop types, pesticide form, diet, and habitat preferences. The sublethal effects of organophosphates and carbamates on birds are manifolds, including malformed embryos, smaller broods, decreased parental diligence,
reduced territorial defence, anorexia and weight loss, subdued immune response,
lethargic behaviour, greater susceptibility to predation, interference in thermoregulation, endocrine disruption, and inefficiency to orient in the proper direction for
migration. Thus, pesticide intoxication reduces the chance of survival and successful reproduction that ultimately perturb to flourish a healthy bird population. The
present review tries to encompass the up-to-date information on the succession of
the anthropogenic use of pesticide and their consequences on selected bird populations, emphasizing organophosphates and carbamates in particular.
Keywords Birds · Organophosphate · Carbamate · Lethal effect · Sublethal effect
3.1 Introduction
The human population of the world is predicted to increase approximately 10 billion
by 2050 (Saravi and Shokrzadeh 2011). With the greater demand for food, intensification of agriculture becomes the primary objective for researchers and implementers. To produce more in the finite land mass, soil amendments (like use of fertilizers)
and application of pesticides (for crop protection, as a whole) are common (Köhler
and Triebskorn 2013; Gill and Garg 2014). Pesticides become indispensable in agriculture and are used for different purposes like crop protection, stored grain, floral
gardens, and eradication of the pests transmitting infectious diseases in plants. Each
year throughout the world, nearly 38 billion USD is spent (12.5 billion USD for the
USA alone) on synthetic pesticides (US EPA 2011; Germany 2012).
A. Mitra et al.