# Emerging Technologies for Degradation of Dichlorvos: A Review
## 2 Toxicological Effects of DDVP  
DDVP has the tendency to remain in solution due to its solubileness, with a limited tendency to absorb sediment. DDVP is subject to both abiotic and biological degradation in solution [20]. In addition, DDVP has the ability to regulate the neurotransmitter acetylcholine which leads to irreversible inhibition of acetylcholinesterase. Thus, it has harmful effect on nontarget invertebrates and vertebrates [21]. Based on the laboratorial research, DDVP can be hydrolyzed to dichloroacetaldehyde, dichloroethanol, dichloroacetic acid, dimethylphosphate, and dimethylphosphoric acid [22]. The process of DDVP degradation in moist soil is similar to that in aqueous solution. There are two main routes of exposure: inhalation and skin contact. People who are brought into contact with toxic waste containing DDVP or use domestic pesticides can potentially be exposed to them by inhalation. Due to its long half-life and current situation of usage, the toxic effects caused by DDVP residue should not be ignored. The toxicological effects of DDVP are presented in Table 1.  
Toxic DDVP exposure in zebrafish was reported by [PERSON] et al. [23], who illustrated various kinds of procedures in energy utilization and stress response in liver. Three concentrations of DDVP show that the effect on liver energy metabolism is rigorously controlled. Toxic exposure may lead to a certain amount of neuromuscular impairment in exposed zebrafish. Moreover, a study on tilapia demonstrated that acetylcholinesterase (AChE) suppression in brain and liver is caused by DDVP which exerts cholinergic action by blocking cholinesterase in the central and peripheral nervous system [24]. Tilapia lived under a sublethal concentration (0.5 mg/L) of DDVP, and all sizes of fish showed a significant inhibition of brain and liver AChE activities. AChE activity was regarded as an indication of the extent of pollution of the aquatic environment by organic chemicals and was correlated with water contamination. Harmful impact on rats according to DDVP have also been investigated as representatives of damage to land mammals. [PERSON] et al. [25] reported a study in which Wistar rats were injected with four different dosages of DDVP dissolved in saline on their neck. Sperm motility is deteriorated by DDVP exposure at different doses, which means humans may suffer from testicular dysfunction. Another study focused on the biochemical and behavioral sequelae of chronic DDVP exposure in rats [26]. This study illustrated that all components of spontaneous locomotor activity in rats exposed to DDVP have reduced remarkably. DDVP administration also led to evident damage on rats' muscle strength and coordination. According to a cellular-level study, exposure to DDVP may result in neuronal cell death in primary rats [27]. This study observed significant upregulation of pro-inflammatory molecules like nitric oxide, tumor necrosis factor alpha (TNF-\(\alpha\)), and interleukin 1 beta (IL-1\(\beta\)) when microglia were treated with DDVP (10 \(\upmu\)M). The study concluded that DDVP can induce microglial activation and then cause cell apoptosis. Another study described the influence of butyrylcholinesteraseerase (BuChE) activity in rats with continued exposure to DDVP [28]. Different types of doses of DDVP (8.0 mg/kg of body weight) were given to both sexes of rats, with two-day intervals between administrations. This study clearly showed that exposure to DDVP significantly decreased the BuChE activity in both male and female rats. There are several reports about the hazardous effects of DDVP on the human body indicating that a higher concentration of DDVP can cause death. A woman died a day after ingesting DDVP and an infant died after ingesting a cake-like bait that contained DDVP [29]. Although most of the studies showed little proof that exposure to DDVP is related to any cancer risk, [PERSON] et al. [2] and [PERSON] et al. [4] indicated the toxic effects of DDVP on human peripheral blood lymphocytes.