Pesticides adverse effects

With the present major emphasis on the preparation and testing of a seemingly endless number of synthetic organic compounds for pesticidal activity and the clamor over their possible adverse effects on public health and our general environment, comparatively few people realize that certain natural insecticides have been used by man for centuries. The ancient Romans apparently utilized false hellebore as a rodenticide and insecticide (13), and preparations of Tripterygium ivilfordii (thunder-god vine) and Derris species have been employed by the Chinese for hundreds of years as insecticides (16). The insecticidal properties of sabadilla (from Schoenocaulon species) were known in the sixteenth century tobacco was in use as... 

Children s Susceptibility. The information on health effects of endosulfan in humans is derived mainly from cases of accidental or intentional exposure of adults to high amounts of the pesticide, and the main adverse effect is neurotoxicity. No reports of adverse effects in endosulfan-exposed children were found, but it is reasonable to assume that children will exhibit similar signs and symptoms to those in adults under similar exposure conditions. Some studies in animals have provided evidence that young animals respond to endosulfan differently than adult animals (Kiran and Varma 1988 Lakshmana and Raju 1994 Sinha et al. 1995,1997 Zaidi et al. 1985), but there is no conclusive evidence to suggest that young animals are more susceptible than older ones. Further studies that evaluate a number of different end points in young as well as older organisms would provide valuable information. 

The purpose of this chapter is not to discuss the merits, or lack thereof, of using plasma cholinesterase inhibition as an adverse effect in quantitative risk assessments for chlorpyrifos or other organophosphate pesticides. A number of regulatory agencies consider the inhibition of plasma cholinesterase to be an indicator of exposure, not of toxicity. The U.S. Environmental Protection Agency, at this point, continues to use this effect as the basis for calculating the reference doses for chlorpyrifos, and it is thus used here for assessing risks. 

Microbial activity can also be stimulated by mineral colloids through their ability to sorb metabolites that would otherwise have an adverse effect on microbial growth (Filip et al. 1972 Filip and Hattori 1984) This may be due to the toxicity of metabolites, and their feed back repression and, encouraging competitors. Predictably, montmorillonite (CEC —100 cmol kg-1 and specific surface of 800 m g 1) is more effective than kaolinite and finely ground quarts. Other substances, such as antibiotics and pesticides that are toxic to some microorganisms, can also be adsorbed by the surfaces of mineral colloids (Theng and Orchard 1995 Dec et al. 2002). 

The relative importance of both activities is well reflected on the population labor distribution per activity 70% is dedicated to agriculture and 15% to shellfish production [14] however, these two activities are not very compatible. Aquatic organisms are currently being exposed to multiple chemical and environmental stressors with different mechanisms of toxicity, each contributing to a final overall adverse effect [16]. Recently, the shellfish farmers in the Ebro River delta have complained about a loss of production in the periods of rice cultivation that they attribute to the heavy pesticide loads discharged after rice field treatment, and this has raised also public concern about the quality of the water in this area. 

The Food Quality Protection Act (FQPA) of 1996 mandated that the US EPA carry out risk assessments that consider the cumulative effects of exposure to pesticides having a common mechanism of toxicity, as well as consider exposure to each pesticide by various routes of exposure (e.g., dermal, dietary, inhalation) and sources (e.g., residues in food and water) in an aggregate manner [19]. To accomplish this, there needs to be sufficient evidence supporting a common adverse effect that is associated with a common mechanism of action in specific target tissues. To date, the required criteria necessary to establish a common mechanism of toxicity with a specific toxic effect for the pyrethroids are not available [1,8,98]. 

Prenatal and postnatal exposures to fenvalerate reduced prostate and seminal vesicle weights and plasma testosterone levels in male rats [55], A chronic study showed no adverse effects on reproductive tissues at a high dose level of 1,000 ppm [142]. In vivo and in vitro studies with rats and mice suggested that fenvalerate may affect male and female reproduction, possibly due to calcium transport alteration [143-146], One paper reported that fenvalerate affected human sperm count and sperm motility of male workers who were exposed to fenvalerate in a pesticide factory [147]. 

Mainly comprised of plant protection products and biocidal products, pesticides are designed to influence fundamental processes in living organisms. They may have the potential to kill or control harmful organisms such as pests, but can also cause unwanted adverse effects on non-target organisms, human health and the environment (EC 2007). Both the hazards and benefits of pesticides are well documented in published literature and have been reviewed most recently by Cooper and Dobson (2007). 

Ecological risk assessment in EIA is to evaluate the probability that adverse ecological effects will occur as a result of exposure to stressors2 related to a proposed development and the magnitude of these adverse effects (Smrchek and Zeeman, 1998 US EPA, 1998 Demidova, 2002). A lion s share of site-specific EcoRAs were concerned with chemical stressors—industrial chemicals and pesticides. 

Federal agencies such as the FDA and EPA require a battery of toxicity tests in laboratory animals to determine an additive s or a pesticide s potential for causing adverse health effects, such as cancer, birth defects, and adverse effects on the nervous system or other organs. Tests are conducted for both short-term (acute) and long-term (chronic) toxicity. For chronic effects other than cancer, laboratory animals are exposed to different doses to determine the level at which no adverse effects occur. This level is divided by an uncertainty or safety factor (usually 100) to account for the uncertainty of extrapolating from laboratory animals to humans and for individual human differences in... 

In this study a series of surface water and deep soil samples were analyzed to detect ai migration or runoff of waste pesticides from typical Chemical Control Centers. Entomological evaluation of soil biota and monitoring of dermal exposure to pesticides of mlxer-appllcators took place throughout the 1980 season. No adverse effects as a result of the Chemical Control Centers were detected. 

Pesticides are used to kill household insets, rats, cockroaches, and other pests. Pesticides can be classified based on their chemical nature or use as organophosphates, carbonates, chlorinated hydrocarbons, bipyridyls, coumarins and indandiones, rodenticides, fungicides, herbicides, fumigants, and miscellaneous insecticides. The common adverse effects are irritation of the skin, eyes, and upper respiratory tract. Prolonged exposure to some chemicals may cause damage to the central nervous system and kidneys [32,33]. 

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