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Abstract Human activities in the area adjacent to Egyptian Mediterranean coast, especially in front of the Nile Delta have been obviously developed and consequently have led to large urbanization and industrial development. So far, the coastal water of the Mediterranean is the main recipient of the effluents of untreated domestic and industrial wastes as well as land drainage, which may influence the ecosystem structure in the coastal waters.Considerable attention has been focused on laundry and cleaning chemicals and the environmental risks associated with their manufacture, use and disposal. Existence of breakdown products of cleaning agents in the marine environment poses an excellent indicator of land-based sources of marine pollution. Linear alkylbenzene sulfonate (LAS) and Boron were chosen as typical detergent ingredients along with total phenols as a representative of the ubiquitous group of xenobiotic organic chemicals used as formula ingredients in household cleaners and personal care products. Also, non-cancer risk assessment methods are typically based on the use of the target hazard quotient (THQ), a ratio between the estimated dose of a contaminant and the reference dose below which there will not be any appreciable risk. The main objective of the present study was to assess the environmental marine pollution by some detergents residues (LAS, phenol and boron) along the Mediterranean Coast of Egypt. To achieve this objective, ten sampling sites distributed along the Egyptian Mediterranean coast were chosen to represent all hotspots of marine pollution. In addition to Bagoush station as a reference site. Samples were collected from these stations seasonally starting from January to December 2014 for water and twice a year for marine sediments and fish ”sardine Sardina pilchardus)” and analyzed for physicochemical parameters, and the household detergent residues according to standard methods. The study area under investigation was sorted on the basis of types of discharging outlets into four groups rather than control station (II). The group A stations represented by stations (I ) in Salloum and station XI in Arish; this group has no land-based sources except for the fishing boats traversing and anchoring, group B stations included stations of Dekhaila (IV) and Eastern Harbour (VI) that receive contaminants from port operation includes ship-related factors such as vessel traffic, ship discharges and emissions, spills and leakage from ships; and cargo-related factors such as cargo handling and storage, handling equipment, hazardous materials, waterfront industry discharges, and land transport to and from the port., group C stations included Nile river branch” (VIII) and Borollus (IX) that receive agricultural wastewater and sewage, and finally group D stations which consisted of stations Nobareya (III), El-Mex (V), Abu Qir bay (VII) and Port Said (X) that receive agricultural, industrial wastewater and sewage. The results of the physico-chemical characteristics of the seawater samples reflected that El-Salloum (Station I; group A) was close to the reference station where it had the lowest values of water temperature (20.0°C), BOD5 (1.5mgl-1), and OOM (7.0 mgl-1) and the highest values pH (8.26), DO (6.76 mgl-1). In contrast, El-Mex (Station V; group D) was the highest in BOD5 (9.6mgl-1) and OOM (28.3 mgl-1), also Port Said (station X; group D) characterized by lowest salinity (30.41PPT) and DO (4.15 mgl-1).Concerning to the marine sediments characterization, for pH values, Dekhaila (station IV; group B) recorded the lowest pH value (7.66) while Noubaria was detected the highest one of 8.12; for the water content, El-Mex (Station V; group D) was the lowest (18.81%) and Port Said (station X; group D) was the highest (22.27%) and for TOM%, Arish (station XI; group A) and Rashid (station VIII; group C) recorded the lowest value of 0.17% while the highest was 0.81% recorded at Eastern Harbour (station VI; group B). Proximate Composition Analysis for the tested fish (Sardina pilchardus). Water content fluctuated between the minimum of 73.91 %detected at station I in Salloum and a maximum of 74.95 % was observed at Nobareya (station III; group D). The lipid contents, Abu Qir Bay (station VII; group D) recorded the lowest value (3.019 ± 0.046%) while Dekhaila (station IV; group B) recorded the highest value of 6.476 ± 0.187 %. The distribution of residual household detergents in the study area Egyptian Mediterranean coast revealed that Arish station (station XI; group A) represented the lowest values of LAS in both surface and bottom seawater (0.69 and 3.19μg/l, respectively), phenol in bottom water (2.97 μgl-1) and sediments (0.053 mg kg−1 dry w), and boron in sediments (7.56 mg kg−1 dry w). While El-Salloum (station I; group A) showed the lowest values of LAS in sediments (0.065 mg kg−1 dry w) and boron in surface and bottom seawater (2.08 and 3.62mg/l, respectively). In contrast, Port Said (station X; group D) was the highest values of LAS in sediment (0.736 mg kg−1 dry w), phenol in both of surface seawater (6.20 μgl-1), sediment (0.244 mg kg−1 dry w) and fish tissues (0.098 mg kg−1 dry w), and boron in both of surface seawater (7.17 mgl-1), sediment (33.26 mg kg−1 dry w) and fish tissues (6.80 mg kg−1 dry w). Estimated results of chronic daily intake (CDI) of studied residual household detergents (LAS, phenol and boron) from tested fish Sardine (Sardina Pilchardus) showed that El-Salloum (station I; group A) recorded the lowest CDI value of LAS 2.25E-05 mg/kg/day while Nobareya (station III; group D) showed the lowest CDI value of both phenol 7.69E-06 mg/kg/day and boron 3.57E-04 mg/kg/day. Brollous (Station IX; group C) revealed the highest CDI values of both LAS3.63E-05 mg/kg/day and boron 1.09E-03 mg/kg/day while Port Said (station X; group D) represented the highest CDI of phenol 1.32E-05 mg/kg/day. So the target hazard quotient (THQ) calculated on the basis of the US EPA 1989 guidelines for the human health risk from consuming the contaminated fish; the HQ is the ratio of the chronic daily intake (CDI) to a reference dose (RfD). THQ values were corresponding to the results of the CDI values. Accordingly, the oral ingestion of boron from Sardine (Sardina Pilchardus) does not pose a human health hazard in the future and the flesh of Sardine Pilchardus still safe for human consumption.Principal component analysis (PCA) for seawater revealed three factors explaining 82.87% of total variance were adopted for studied parameters in Seawater. Factor1 (42.55%) had a high positive factor loading for BOD (0.845) LAS SW (0.923), LAS BW (0.935) , TPBW (0.894) and OOM (0.837) and moderate loading to TPSW (0.673) but, high negative loading to Salinity (-0.744). Factor 2 (27.47%) had a high positive factor loading to Boron in surface and bottom seawater with loading values (0.841) and (0.898 ) respectively and moderate loading to temp (0.765), negative loading to dissolved oxygen (-0.78). Factor 3 (12.85%) possessed a positive loading to pH variations (0.809). Sediment showed three factors explaining 82.87% of total variance were adopted for studied parameters in marine sediments. Factor1 (43.01%) had a high positive factor loading for LAS (0.877) TP (0.866) and B (0.953) . Factor 2 (24.82%) had a high positive factor loading to WC% with loading values (0.891). Factor 3 (12.85%) possessed a positive loading to organic matter (OM%) variations (0.956). and for tested fish Sardine (Sardina pilchardus) the PCA results showed two factors explaining 78.78% of total variance. Factor1 (43.33%) had a high positive factor loading for lipids (0.843), LAS (0.923) and B (0.668). Factor 2 (35.45%) had a high positive factor loading to WC% with loading values (0.891). Cluster analysis (CA) grouped the studied parameters into two main clusters (A&B) based on similarities within a group and dissimilarities between different groups. Cluster (B) includes PH, DO,PH Sed., Salinity and W.C% Sed. In cluster (A) it was divided into two sub-clusters (C&D). Cluster (C) includes Temp, LAS Sed, B S water, B B Water, while cluster (D) includes the most number of paramters (BOD5, O OM, LAS BW, LAS SW, OM%Sed, TP SW, TP BW, Tp-Sed and B-Sed). The results obtained from PCA and CA are similar, which indicated that the LAS, Phenol and boron may be originated from same source. Another Cluster analysis was performed according to similarities in condition of the stations. Cluster analysis (CA) grouped the studied stations into two main clusters (A&B). Cluster (A) includes Bagoush, Salloum and Arish, which are identified as clean or pristen area. Cluster (B) divided into two clusters (C&D). Cluster (C) includes (Nobareya, Dekhaila and El-mex), which have the same conditions and structure, (Borollus and Rashid) have the same source of pollution and cluster (D) which includes (Eastern Harbor, Abu Qir Bay and Port Said), they are similar in discharge and drainage sources. The study concluded that the distribution pattern of the selected detergents residuals revealed that the concentrations increased downward i.e., sediments > bottom water > surface water. Boron represented the most persistent residual followed by LAS then phenol. The seasonal variation of the levels of detergents residues at the study area along the Mediterranean coast of Egypt may be arranged in the order of: autumn > spring > winter The high concentrations of the selected residual of household detergents observed in group D stations may be attributed to the influence of the discharge of wastewater partially or without treatment directly to the coastal water where this group is highly urbanized. The levels of LAS, total phenol and boron did not pose any potential human hazard Based on the results obtained from the present study, the following recommendations could be greatly helpful in the protection and improvement the quality of coastal environment as well as the public health: 1. Monitoring of coastal areas is a principal to protect the marine environment.2. Give more attention to the wastewater treatment prior to the discharge into the marine environment. 3. Enhance the environmental awareness towards the best laundry practices e.g. reduce the consumption of detergents specially during summer.4. Encourage the production the eco-friendly detergents with the specification of non-toxic, non-persistent, safe degradation products. 5. Recycling of gray water to avoid the high concentration of detergents discharged into aquatic environment.6. Further studies needed to assess the effects of these detergents residues on another fish species. |