Available online freely at www.isisn.org Bioscience Research Print ISSN: 1811-9506 Online ISSN: 2218-3973 Journal by Innovative Scientific Information & Services Network RESEARCH ARTICLE BIOSCIENCE RESEARCH, 2019 16(3): 3258-3274. OPEN ACCESS Pathological effect of water polluted with heavy metals and fish parasites on Carangoides bajad (Forsskål, 1775) from the Red Sea coast of Rabigh region, Saudi Arabia El Jawaher A. Bin Dohaish1 and Areej O. Bakhraibah2 Department of Biological Science, Faculty of Science, University of Jeddah, Saudi Arabia, 1https://orcid.org/0000-0002-1094-0675 2https://orcid.org/0000-0001-8865-3134 *Correspondence: [email protected] Accepted: 11 Sep. 2019 Published online: 30 Sep. 2019 Pollution of the ecosystem is a source of concern and wide attention globally. In this study, samples of water was collected and 50 fish samples of Carangoides bajad to assess the rate of water pollution of the coastal area of Rabigh on the coast of the Red Sea and that is due to its closeness to industrial activities. Concentrations of some heavy metals were assessed and was estimated as follows Zn > Fe > Pb (81 > 15.1 > 12.6 μg/l, respectively) using atomic absorption spectrophotometer (Model AA-7000, Shimadzu, Japan). Using a light microscope, different types of endoparasites and ectoparasites were recognized in the chosen infected fish; in addition, a histological examination was conducted for some targeted organs (gills, intestines, liver). The results revealed that 40 fish were infected with subclass Copepoda Hatschekia (intensity 2); digenean parasites Bucephalus margaritae (intensity 4.36), Plagioporus ira (intensity 3.09), and Tergestia bengalensis (intensity 2.33); and Anisakis physeteris (intensity 12.57). The results revealed many histopathological changes which demonstrate the presence of potential risks on consumers due to pollution of the aquatic ecosystems. Therefore, continuous monitoring of these pollutants is an essential matter to ensure the safety of aquatic organisms and humans that rely on these aquatic resources. Keywords: water pollution; heavy metals; parasite; gills; liver; intestines. 1. INTRODUCTION substances with heavy metals that increase Environmental concerns raised by human toxicity (Kleinertz and Palm, 2013). activities that do not consider the nature of Parasites are key elements in the aquatic ecological systems are gaining considerable ecosystem that aid basic ecological processes research attention globally. Although we rely such as the composition of food webs, on aquatic resources in several industries biodiversity and productivity of the ecosystem such as the manufacturing, food, and (Poulin, 1999; Marcogliese, 2004). Therefore, entertainment industries, these activities an ecosystem that has good performance and pollute the environment by dumping industrial flexibility (Costanza and Mageau, 1999) is a waste, combustion products, and other system enriched with various types of Bin Dohaish and Bakhraibah Effect of water polluted with heavy metals and parasites on Red Sea fish. parasites (Marcogliese, 2005; Hudson et al. production of mussels because of the elevated 2006). degrees of pathogenicity of the larvae (Da Parasites are important components of Silva et al. 2002). Bucephalosis destroys the ecosystem and play a significant role in reproductive tissues of the host and disables biodiversity. They provide valuable information its gametogenesis leading to its castration about their hosts and the environment in which (Coustau et al. 1990) and possibly, its death they exist. Studies on Hatschekia (Poche, (Da Silva et al. 2002). As mentioned by 1902) in marine fish from various regions of Nahhas et al. (2006), the diagnostic character the world have received considerable attention for B. margaritae is the presence of seven since the turn of the century. The family tentacles, each containing two projections, Hatschekiidae (Kabata, 1979) (Copepoda: one big and basal and the other small and Siphonostomatoida) is one of the major gill distal. Bucephalus can be found worldwide in parasitic groups in marine fish. Hatschekia tropical and subtropical waters such as in the (Poche, 1902) is the largest genus of this Arabian Gulf off the coast of Kuwait, Red Sea, family with 176 valid species recognized by Arabian Sea, Philippines, Hawaii, India, and the World Register of Marine Species (Walter Japan (Nahhas et al. 2006; Amato, 1982; and Boxshall, 2019). Although these Chinchilla et al. 2006). copepods produce a small amount of eggs, Tergestia bengalensis was first discovered they are capable of infecting several fish by Gupta and Singh, (1985) and classified species and often accumulate on their host in under the genus Tergestia. It has been large numbers (Jones, 1998). The parasites previously reported in C. bajad species as well on the gills of fish can cause extensive gill (Bakhraibah,1999). Although this genus is damage and severe hemorrhaging with found frequently in the intestines of hosts and inflammation and exsanguination caused by is usually present in large numbers, only a few their attachment and feeding habits (Lester were present in our host fish. Further, there is and Hayward, 2006). a lack of sufficient literature on the Digeneans with their heteroxenous life characteristics and effects of this parasite. cycle have not only a definitive host but also Anisakis physeteris (Baylis, 1923) is a primary (mollusk) and secondary (fish) hosts. species of the parasitic nematode of the Plagioporus is a genus of Trematoda class subclass Digenea, of family Anisakidae, which parasites and subclass Digenea. The species is commonly found in the intestines and liver of this genus, such as Plagioporus ira of its hosts. Anisakis physeteris is not host (Yamaguti, 1940), occurs in both marine and specific and can be transmitted through the freshwater teleosts around the world, and was ingestion of other infected crustaceans. Adult first identified in Choerodon azurio. Parasites parasites usually appear in pinnipeds and transmitted through the food chain alter their cetaceans. This parasite is temperature hosts to increase virulence, and thus, they dependent; under low environmental enhance parasitic transmission. Increase in temperatures, there is a decrease in the virulence enables the parasite to increase its number of larvae penetrating the fish. Larval reproductive output. This increases their stages in fish tend to be more prevalent in prevalence and abundance rates in addition to areas where various hosts are available in their pathogenicity (Price, 1980). large numbers such as in inshore waters The digenetic trematode, Bucephalus (Smith and Wootten, 2012). margaritae, was first described by Ozaki & In recent years, there has been an Ishibashi, (1934); it was also previously increased focus on identifying the correlation identified in the intestine of Carangoides bajad between parasitism and pollution, studying the (Bakhraibah,1999). Linnaeus, (1758) showed role of parasites as biomarkers of pollutants that Bucephalus larvae in Perna perna mussel and the health of the ecosystem, and the on the coast of Santa Catarina caused severe interaction between parasites and their hosts. effects on the culture and commercial Parasitism increases the ability of the host to Bioscience Research, 2019 volume 16(3): 3258-3274 3259 Bin Dohaish and Bakhraibah Effect of water polluted with heavy metals and parasites on Red Sea fish. intake toxic pollutants. An increase or received increasing research attention in the decrease in pollutants can cause an increase last couple of decades. In this study, we or a decrease in the prevalence of the detected the concentration of heavy metals parasites, thus, making parasites effective (Fe, Pb, and Zn) to assess the state of biomarkers for pollution in an environment with pollution in the coastal area of Rabigh on the heavy metals (Goater et al. 2013; Sures et al. Red Sea coast, to identify the relationship 2017). between the heavy metal concentration and Studies have focused on the potential parasites and to determine the potential risks roles of parasites as biomarkers of the quality for fish considered as biomarkers of the of water and their suitability as biomarkers of pollution level of the coastal water of Rabigh. the quality of the environment (Vidal-Martínez Food is a vital source for heavy metals et al. 2010); other studies have focused on the accumulation in biological waters (Clearwater use of fish parasites as good organisms for the et al. 2000). Heavy metals are transported biological monitoring of heavy metal pollution through the food chain, which affects the in the aquatic environment (Sures et al. 2017). health of the consumers. An accumulation of The aquatic environment can be studied either heavy metals in humans can cause chronic directly, through regular monitoring for quality and acute damages in the local communities, markers of the water, or indirectly, by using thereby reducing growth and reproductive biological factors such as fish parasites ability (Schulz and Martins-Junior et al. 2001). (Bayoumy et al. 2015). This study aims to determine and investigate The quality of water is considered an the concentration of heavy metals and its important factor that helps determine the relationship with parasites in the waters in the prevalence of parasites (Authman et al. 2008); Rabigh region. This region is located near it can enhance the presence of the parasites petrochemical industries and effluent in an increasing manner in aquatic