As a result of the potential bioaccumulation and toxicity of many aquatic organisms, the effect of metals on aquatic ecologies is still considered an essential threat for human health. While metals are widely regarded as contaminants, the awareness that they are natural substances is significant. The essential factor, for example, is zinc of at least 150 enzymes; the usual function of cytochrome oxidase is basically copper; the red blood cells have iron part of a hemoglobin; the plants need only the boron [1].There is good evidence of accumulation of heavy metals in marine invertebrates exposed to environmental contaminants [2-6]. A number of investigators [7-11]. Concluded, as they are able to accumulate large amounts of metals in tissues, that water snails (such as (Bulinus globosus e.t.c) are considered suitable for diagnosis of heavy metal-contaminated sites (pollutant tests) in the tissue. Heavy metal accumulates in earthscrews (such as A. marginata etc.) and can be used for urban heavy metal surveillance. Snails are a very suitable diagnostic tool in heavy metal contaminated regions. Many studies [12]. Have shown that land snails can accumulation in their foot and digestive gland tissue high levels of copper, zinc, cadmium and lead. Land-scape snails can be used as models invertebrates to accumulate Cu, Zn, Cd and Pb in terrestrial habitats in environmental monitoring [13]. Snails are important protein sources and are eaten by a large majority of the people in the dense tropical forests and the neighboring towns, which are currently the main concern of people in snail farming. The meat of soil snails is very nutritious. Fleece has a low cholesterol content and is a source of minerals which must be produced and preserved normally. The snails can be used as bioindicators for pollution by heavy metals by aquatic ecosystems. They store bioavailable metals in their organs and have a strong organotropic effect on the digestive glands and kidneys [14,15]. The aims of this analysis were to classify the snail species in the area of research, to determine the physiochemical parameters in the soil in Igbekebo area, to assess the concentration of elemental concentration present in the Igbekebo area of study in soil and freshwater snails. Several authors have pointed out the value of molluscan as good indicators to track heavy metal pollution, even though the abnormally high environmental heavy metal concentrations impact many bio-processes involved in molluscan population growth and maintenance such as feeding, rising, breeding, overall physiological activities and maturity [16-21]. Bioavailability and accumulation and effects of heavy metals and radioactive elements in sediments and soil and water were analyzed [22-28]. With a special reference to the estuaries of the UK. Research has shown that different heavy metals such as Pb , Cr, Sn, Ag, Cd, As, Cu, Sn, Zn) were found in the selected estuary through fresh molluscs. The presence of certain selected heavy metals, for example; Pb, Zn, Cd and Cu from the tissues of Helix aspersa was analyzed according to [17]. The digestive glands of the molluscs have been shown to store Pb, Zn and Cd more uniformly when Cu is distributed over the animal's tissues. These results demonstrate that the digestive gland selectivity for Cd is higher than that of either Cd or Pb and that analysis of the mollusc digestive gland can be useful for the study of Cd levels at various sites Bioassessments and possible health threats in land snails, widely used in Bayelsa State, Nigeria were also assessed [29]. Including the possibility of identified heavy metals in the land snails (i.e. Cu, Zn, Fe, Pb, Cu, Zn and Fe). Research has shown that the Hazard Index values indicate potential adverse health risks by consuming land-snail species in that area.The human-risk evaluation in snail (Archachatina marginata) was assessed in 4 contaminated areas of the rivers in Nigeria according to [30]. (Archachatina marginata) Cadmium, lead, chromium, nickel, zinc and manganese are the selected heavy metals.The Heavy Metal concentrations in muscle tissue were measured from different regions and the Approximate Daily Consumption and Target Hazard Quotients were assessed for possible non carcinogenic health risks to consumers. The cadmium and platinum (ranged between 0.50 – 0.65 and 2.60-5.00 kg / person / day) in snail captured at different sites were higher than the referred doses established below Nickel, Manganese, Zinc and Chromium respectively.The links between crude oil exploration and environmental impacts have been reported in Nigeria and are of relevance to the collection of qualitative data and analysis for improved rural economy. The Igbekebo region of Niger Delta was studied precisely to determine the oil spillage level in the area in Apata in 2010 According to this study. It appears in the study that the area needs urgent cleanup. A snail is a shelling gastropod in loose words. The name is most widely used for land snails; land pulmonary gastropod molluscs.It not only includes land snails, but many species of marine snails and freshwater snails. There is significant human relevance to snails, including as food, as pests, as disease vectors, and their coats are used as decorative objects and incorporated into jewellery. Previously used for estimating terrestrial pollution [31]. Snails such as the Cornu aspersa (Syn., Cantareus aspers, Arianta arbustore, Xeropicta arenosa and Eobania vermiculata) have been used as their ability to accumulate organically-organic heavy metals and pollutants into their tissues [32]. Snails of Cornu aspersum species are among the most commonly used snails on the Mediterranean region, western Europe, northwest Africa and eastern Asia, although their versatility is also correlated with intraspecific shell variations, reproductive system, and biological cycles [33].

Study Area

In Ondo State, Nigeria, Igbekebo is the seat of the Local Government District. It is inhabited by the Western Apoi and Arogbo peoples of the Ijaw (Izon) ethnic sub-groups. It has an area of 762 km2 and, at the 2006 census, a population of 154,978. Due to fishing practices and lumbering operations, the river of Igbekebo has a strong economic impact. Because of the chemical and biological sources in the water, the river is heavily contaminated and this will result in elevated heavy metal concentrations. Igbekebo is an area producing oil which, due to the bunkering activities carried out in the area, makes it very contaminated due to oil spillage. It is a small rural village that does not have any commercial activity

Figure 1: Map Of Study Area.

Sampling

The land is the Igbekebo oil palm plantation and the water is the Igbekebo River. Two places have been taken for sampling, which is land and water. Snails were collected at the first site, which is the canal, and water samples were collected at five (5) separate sites using plastic bottles. Sample A was labeled for the snails and position 1-55 was labeled for the water samples snails were obtained for the second field, the oil palm plantation, and the soil samples were also taken with plastic spoons in a polythene bag at five (5) separate locations at a depth of 10 cm. The snail sample was marked as sample B and the soil sample was marked as site 1-5. The different sampling locations are shown in Fig 1 and this map had used for other study by Ediagbonya et al [34].

Sample preparation

The snails were oven-dried for 6 hours at 1050C and then crushed into tiny particles (powdery form) and set up for examination. The soil samples were air-dried and ready for analysis for three days, and the water sample was also primed for analysis.

Proton Induced X-Ray Emission(PIXE) was used for elemental analysis. Portable pH and conductivity [35]. Meters were used to assess the pH and electrical conductivity of the extracts. Nitrate and chloride were also measured using standard methods [36]. Details of the elemental analysis had reported [28,24].

Bio accumulation factor (BAF) describes the intake and distribution of the ingredient in an organism in a given environmental matrix after exposure [37]. And was used here to assess the level of snail with higher health risk [38]. It is measured as the snail factor concentration in the soil [25,34,39,40]. BAF = C (snail)/C (soil)

The risk was assessed by using the target hazard quotient (THQ) and the hazard index(HI).To compute the risk for human health derived from ingesting contaminated food as given by FAO/WHO [41]. And the target hazard quotient (THQ) provided in the USEPA Region III Risk-based concentration table (USEPA, 2015). The THQ was computed by using the formula given by (Singh et al., 2010).

Efr is exposure frequency assumed to be 365days year−1, ED is exposure duration in 54 years an average lifetime for Nigeria, while the average body weight used was 65 kg for this study [42]. FIR is average daily consumption taken as 1.95 x 10-2 kg person-1day-1C is concentration of metal in snail sample in mg/kg, RfDo i is the oral reference dose ( Al, Ti, V, Cr, Mn, Co, Pb, Cd, Cu, Zn, Fe and Ni [43,44]. And ATn is average exposure time for non-carcinogens and is taken as 19710 days. The hazard index (HI) from the consumption of snail estimated as the sum of THQs of all the metals in the snail and was expressed as follows;

HI = THQAl + THQTi + THQV + THQCr + THQMn + THQFe + THQCo + THQNi + THQCu + THQZn + THQCd + THQPb

As estimated by [45,46]. The Geo Accumulation (Igeo) index is intended to quantify the level of soil contamination. It was used in [Cn/1.5xBn] by Igeo = In [26, 28]. In sediments, the measured metal 'n' content is Cn and Bn is the history concentration of the same metal.

The enrichment factor (EF) is used to calculate elevated metal concentrations in sediments andsoil in order to measure the level of soil and sediment contamination. In this study, Al andSi were used as reference components. Few writers have used the reference functionality of theseelements [47,48]. According to Ergin et al [49] the metal EF is graded as follows:

Where X/Al is the heavy metal concentration ratio (X) to the concentration of Al.

Wedephol was taken from the reference crustal ratio of the shale value or lithology [50].

For the statistical analyses in this report, IBM Statistical Package for Social Sciences (SPSS) version 24.0 was used. Descriptive statistics such as range, mean, standard deviationat the various sampling locations for the psychochemical parameters as well as heavy metals One direction Variance Analysis was used to conduct the spatial variation of heavy metal means at the various sample sites where substantial difference was found to distinguish significant means was used by the Duncan Multiple Range Test (DMRT). The physicochemical parameters, usingthe Pearson correlation, were also associated with the toxic elements. Principal Component Analysis was the multivariate analysis performed for source identification of heavy metals. The level of significance was set at p<0.05.

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