Page 97 - Veterinary Toxicology, Basic and Clinical Principles, 3rd Edition

64 SECTION | I General

VetBooks.ir rhododendron (Rhododendrum hirsutum), tiger lily TABLE 4.3 Deaths Due to MIC and Reaction Products
(Lilium tigrinum) jessamine (Jasminum officinalis) and
During the Bhopal Gas Tragedy
tansy ragwort (Senecio jacobaea) have been reported.
Oleander has been responsible for poisoning in dogs
Deaths Numbers
(Berny et al., 2010).
In certain Asian countries, kerosene is commonly used Human deaths 2500 a
because solid fuels—biomass (wood, agricultural resi- Buffalo 790
dues, and animal dung) and coal—are major household
Cows 270
energy sources, often burned indoors without chimneys or
smoke hoods. Kerosene use for cooking and lighting Goats 483
remains widespread. Globally, households still rely on Dogs 90
kerosene or other liquid fuels for lighting (Mills, 2005; Horses 23
Fullerton et al., 2008). There seems to have been little, if
a Unofficial figure.
any, systematic study of the exposure implications and
Source: Data from Gupta, P.K., 2004. Pesticide exposure Indian scene.
hazards of household kerosene combustion. In the absence Toxicology 198, 83 90.
of any systematic survey, the extent to which these fuels
cause long-term damage, including morbidity and mortal-
ity in companion animals, is currently unclear (Ritchie with respiratory, ophthalmic, and psychological morbid-
et al., 2003; American Petroleum Institute, 2010). The ities. The cause of death was pulmonary edema and sec-
scarcity of adequate epidemiologic and exposure investi- ondary respiratory infections (bronchitis and bronchial
gations as well as the potential for short- and long-term pneumonia). Epidemiological studies in humans revealed
exposure to household products and chemicals suggest a maternal-fetal deaths, gynecological disturbances and
need for agencies to collect epidemiological data on spontaneous abortion, higher incidence of abnormal uter-
human beings and animals (Nicholas et al., 2012). ine bleeding, evidence of chromosomal aberrations and
genetic defects, and suppression of cell mediated immu-
nity. However, there is no report available on an epidemi-
METHYL ISOCYANATE (UNION CARBIDE ological survey on long-term adverse effects of MIC in
animals (Gupta, 2004).
PLANT DISASTER IN BHOPAL)
Thirty-two years ago, on the night of December 2, 1984, FEED ASSOCIATED TOXICANTS
at approximately 0.30, an accident at the Union Carbide
pesticide plant in Bhopal, India, released at least 30 tons Cross-contamination, resulting from the carry-over of
of a highly toxic gas called methyl isocyanate as well as a undesirable trace amounts of pharmacologically active
number of other poisonous gases. The pesticide plant was ingredients from a medicated/supplemented feed to a non-
surrounded by shanty towns, leading to more than medicated/nonsupplemented feed, may occur at different
600,000 people being exposed to the deadly gas cloud stages of the production process, during the storage, and
that night. The gases stayed low to the ground, causing transport but also on the farm (Gupta, 2006; Abdulkaf
victims throats and eyes to burn, inducing nausea, and et al., 2015). The consumption of a feed, containing
many deaths. An estimated 8000 people (official fig- a pharmacologically active ingredient due to cross-
ure 2500) and 4000 animals died within minutes of expo- contamination, by a nontarget species such as the laying
sure to the gas, and a rough estimate of 15,000 animals hen and production animals may generate unwanted resid-
suffered toxic effects but survived (Mehta et al., 1994). ual concentrations of these substances in edible matrices.
The breakup of human and animal deaths is summarized Ionophores such as monensin, lasalocid, narasin, and
in Table 4.3 (Gupta, 2004). salinomycin are frequently used as feed additives and coc-
Thirty-two years later, toxic material remains, and cidiostats for cattle, sheep, and poultry (Kamashi et al.,
many of those who were exposed to the gas have given 2004, 2005). Contamination of feed with antibiotics, pes-
birth to physically and mentally disabled children. There ticides, metals, and with other toxins is quite common
has, however, been no long-term epidemiological survey (Muhammad et al., 2009; Nisha, 2008). Although compar-
that conclusively proves that birth defects are directly ative toxicity was difficult to estimate, most cross-
related to the drinking of the contaminated water or toxic comparisons within and across species indicates relative
agents of the explosion are involved (Gupta, 2004). toxicities of the ionophores from lowest to highest were
The acute toxicity of inhaled MIC or its reaction pro- salinomycin , lasalocid , or 5 narasin , or 5 monensin
ducts was devastating: most fatalities occurred during the (but lasalocid , monensin) , maduramicin (Oehme and
first week. The common acute symptoms were associated Pickrell, 1999). There is some evidence to suggest that