Comparative Evaluation of Heavy Metal Concentration in Water and Sediment, Choba Segment of New Calabar River, Port Harcourt, Nigeria

The coastal waters of Palu Bay are vulnerable to pollution from various activities of the surrounding population. This study aimed to determine the content of heavy metals Pb, Cd, and Cu in the water and sediment of the coastal waters of Palu Bay. The analysis of heavy metal content (Pb, Cd, and Cu) in water and sediment was conducted using an Atomic Absorption Spectrophotometer (AAS). Based on the research, the results showed that the heavy metal content in the water ranged from undetected to 0.04 mg/L for Pb, undetected for Cd and Cu. The heavy metals content in the sediment ranged from 2.17 to 13.8 mg/kg for Pb, undetected to 0.17 mg/kg for Cd, and 5.02 to 37.67 mg/kg for Cu. The Pb content in the water has significantly exceeded the quality standard as stipulated in the Minister of Environment Decree No. 51 of 2004. The Pb content in the sediment is still within safe limits according to Canadian quality standards. The Cd content in the sediment exceeded the quality standard at station 6, while for the other 9 stations, it was not detected. The Cu content in the sediment at 5 stations (2, 3, 4, 5, and 10) has exceeded the Canadian quality standard of 18.7 mg/kg.

The Houjing River flows through Kaohsiung, the most industrialized city in southern Taiwan. In this study, heavy metal concentrations in water and sediments from samples along the river were investigated to illustrate metal contamination levels and call for the awareness of industrial pollution prevention. The heavy metal concentrations in the water samples were low and appear to pose little direct risk to aquatic life and irrigation, but heavy metal concentrations in the sediments are locally very high and present an environmental risk. Cadmium, Cu, and Zn were found in higher concentrations in the river sediments than those recommended in some sediment quality guidelines and findings of river sediments in similar studies worldwide. Hence, the ecological risk of heavy metal contamination in sediments was assessed using the pollution load index (PLI) and potential ecological risk index (RI). Three of the eleven sites sampled were found to have PLI values higher than 1 and 8 of them had ‘considerable’ to ‘very high’ RI values, suggesting a considerable ecological risk. These findings provide an insight into elemental metal contamination of the Houjing River and present a baseline data set, which will be critical for future development and environmental protection plans devised for the region.

The Chironomidae family, known as "non-biting midges" in their adult stage and "bloodworms" in their larval stage, consists of diverse dipteran insects inhabiting various global aquatic environments. Despite extensive global research, data on Chironomidae in the polluted Nyanza Gulf of Lake Victoria, Kenya, is scarce, and molecular identification methods have not been explored. This study aimed to quantify heavy metal concentrations in water, sediment, and insect samples and assess their impact on Chironomid species identified using mitochondrial DNA barcoding of the cytochrome oxidase subunit 1 (COI) gene. Analysis of Variance was used to determine if there were any statistically significant differences in heavy metal concentrations across different sample types or locations along the pollution gradient. Chironomids were collected from Nyanza Gulf, focusing on a pollution gradient. Results showed that concentrations of arsenic (As), lead (Pb), and cadmium (Cd) in insect, water, and sediment samples exceeded standard limits, while mercury (Hg) concentrations were within limits. Significant variations (p ≤ 0.05) in Pb levels were observed in water samples, and heavy metal concentrations in sediment samples varied significantly (p ≤ 0.05), with Pb showing the highest variation (p ≤ 0.0001). Insect samples exhibited significant differences (p ≤ 0.0001) in As and Hg contents. Genetic analysis identified two known species: Chironomus transvaalensis at the heavily polluted Kisumu station and Chironomus pseudothummi at the moderately polluted Kendu Bay and Homa Bay stations. Additionally, a unique Chironomus species was found on Ndere Island, a relatively clean site with restricted human activities. Sequence comparisons indicated proximity to global data but also highlighted the evolutionary significance and uniqueness of the identified species. This study demonstrated the potential use of genetic methods in determining Chironomid species diversity, community structure, and abundance in relation to heavy metal concentration. It suggests that heavy metal pollution may act as a selective pressure, driving the evolution of Chironomid species. The study recommends combining genetic approaches with other pollution sources for a comprehensive understanding of using this species in monitoring pollution

Impact of a catastrophic flood on the heavy metal pollution status and the concurrent responses of the bentho-pelagic community in a tropical monsoonal estuary

Low-, middle- and high-income countries, exhibit indications of risks associated with water quality. The study investigated heavy metal concentrations in surface water and sediments within the Ngerengere River and its tributaries (Kikundi, Bigwa, and Morogoro) drain within in the Morogoro Municipality of Tanzania, an Urban Catchment Area (UCA) with limited available data mainly because of inadequate monitoring and reporting capabilities. Analysis of health and ecological risks associated with heavy metal pollution was also carried out using health risk assessments models, pollution indices, and multivariate analysis techniques. Between the dry and wet seasons of 2023, water and sediment samples from (13) sampling stations strategically established along the Ngerengere river and its tributaries were analyzed for six heavy metals (Pb, Cr, Ni, Cd, Cu and Zn) using the Atomic Absorption Spectrophotometer Model Perking Elmer 850 Graphite Furnace and Perking Elmer AS 800 Auto-sampler coupled with a computer interface for operational, displaying and reading the results. The calculated degree of water contamination (Cd) values in river water in both dry and wet seasons ranged from 0 to 6.803 indicating low and high degrees of contamination respectively. Heavy metal concentration in sediment decreases in the order of Zn>Ni>Cr>Cu>Cd>Pb. The non-cancer risk index (HI) via ingestion and dermal pathways in dry and wet seasons for both children and adult groups was <1 hence no non-cancer risk, However, cumulative dermal and ingestion exposure in both children and adults indicated potential cancer risk in dry and wet season. The analysis of ecological risks associated with heavy metal enrichment in the sediment indicated high enrichment of sediments with Cd, Ni and Zn. Conclusively, in wet months, risk indices tend to be low, while in dry months, they typically remain high.

Heavy metals in water, sediment and tissues of Leuciscus cephalus from a stream in southwestern Turkey

Heavy metals impair water and sediment quality and thus, can cause adverse impacts on aquatic organisms especially when they exceed the recommended threshold levels. Heavy metal concentrations in water and sediments are a reflection of the anthropogenic activities on the watershed as well as the geology of the area. Metal concentrations and subsequently their bioavailability are influenced by the sediment characteristics including particle size and total organic carbon among others. This study determined the concentration of heavy metals - cadmium (Cd), copper (Cu) mercury (Hg) and lead (Pb) in the sediments in relation to grain size and total organic carbon in Lake Baringo. Samples were collected from five sites using a grab sampler and analyzed for total heavy metals using AAS. Particle size classification was done using the sieve method, while organic carbon (OC) was estimated using the Loss on Ignition (L.O.I) method. One way ANOVA revealed significant difference in mean Cu concentrations amongst the sampling sites at P<0.05 (F (4, 14) =6.945 p=0.01). However, there was no significant differences in the levels of Cd and Hg, that is, F (4, 14) =0.03, p= 1.0 and F (4, 14) = 0.36 p=0.83 respectively. However, there was no significant difference in the levels of Cd and Hg. Sites with higher percentages of silt and clay recorded a higher concentration of Cd and Cu as well as percentage of TOC. The results indicated the pollution of the lake by heavy metals presented an ecological and a human health concern requiring monitoring. Key words: Sediment quality, heavy metals, particle size, total organic carbon.

Heavy metal pollution is one of the problems that often occurs in Indonesian coastal waters. Comparative methods of looking at heavy metal content in coastal sediments include a way to show similarities and differences between one or more articles by using certain criteria. Different comparison methods to see the heavy metal content in sediments include the AAS (Atomic Absorption Spectrophotometer) method, AAN (Netron Activation Analysis), Regression, and USEPA methods. Based on the comparison of 2 methods, namely: AAS and AAN methods, the most efficient in analyzing heavy metals in sediments in coastal areas is the Atomic Absorption Spectrophotometry (AAS) method compared to the Neutron Activation Analysis (AAS) method.Keywords:CoastalSedimentHeavy MetalSpectrophotometer

Heavy metals distribution in the bottom sediments of Nizampatnam Bay -Lankevanidibba Coast, East Coast of India

Heavy metal concentrations in sediment, water and fish in two major rivers (Ankobra and Tano) in major farming and artisanal gold mining areas in Ghana1University of Ghana, Accra, Ghana, 2University of Michigan, Ann Arbor, USABackground: Arsenic (As), mercury (Hg) and lead (Pb) are toxic heavy metals that occur naturally in the environment. However, their levels are on the rise due to anthropogenic activities, including artisanal gold mining thus polluting fresh water bodies and posing a threat to aquatic wildlife, animals and humans.Objective: The aim of the study was to assess As, Hg and Pb concentrations in sediment, water and fishes from the Ankobra and Tano Rivers in the Western Region of Ghana, where human activities; especially artisanal gold mining are suspected of grossly polluting river bodies..Methods: Levels of As, Hg and Pb in different fish species and aquatic media (water and sediment) from the Tano and Ankobra River basins were analysed using the Atomic Absorption Spectrophotometer (AAS) Pinnacle 900T (Perkin Elmer, USA). Statistical analysis was done using Microsoft version 10 excel spread sheet and STATA software version 13 (StataCorps LP, Chicago, USA).Results: Overall, levels of heavy metals were in the order, Hg&gt;As&gt;Pb across study sites. Mean concentrations of Hg and As were highest in fish (2.09±1.29 mg/Kg) and (2.80±1.52 mg/Kg), followed by sediment (1.40±1.78 mg/Kg) and (0.61±0.40 mg/Kg), and water (0.09±0.36 mg/L) and (0.06±0.05mg/L) respectively. Pb levels were highest in sediment (1.46±4.26 mg/Kg), followed by water (0.14±0.10 mg/L), and then fish (0.11±0.11 mg/Kg) respectively. Conclusion: As and Hg levels in both Tano and Ankobra were above the WHO recommended levels for pristine freshwater ecosystems and may therefore pose a threat to aquatic wildlife and human health. Keywords: Tano, Ankobra, Heavy metals, artisanal

Concentrations of heavy metals (Cd, Cr, Cu, Ni, Pb, and Zn) were measured in water, sediments, Ceratophyllum (hornwort), and Bellamya sp. (edible snail) from residential, mixed (industrial and commercial), and agricultural areas with rural rivers in the Taihu Lake region, China. Zn concentrations were the highest, whereas Cd concentrations were the lowest among the six metals in water, sediments, and aquatic organisms. Cd was mainly present in the acid-soluble fraction, Cr in the residual fraction, and Pb in the reducible fraction of sediments. Heavy metal concentrations in water, sediments, and aquatic organisms in the three areas followed the order of the mixed area > residential area > agricultural area. Heavy metal concentrations in aquatic organisms were not only related to total metal concentrations in water and sediments but also to metal speciation concentrations in sediments. In addition, the bio-concentration factor (BCF) values of Cr, Cu, Pb, and Zn for Bellamya sp. were higher than those for Ceratophyllum, whereas the BCF values of Cd and Ni for Bellamya sp. were lower than those for Ceratophyllum. An ecological risk assessment of heavy metals in sediments showed that Cd posed the highest ecological risk to the environment. A health risk assessment showed that consuming Bellamya sp. from the mixed area could cause a potential health risk.

Heavy metals concentration in water and sediment was investigated at the Motor Park Area and New Bridge Site of lower River Benue, Ibi, Taraba State. The heavy metals levels were examined using atomic absorption spectrophotometer (AAS) Buck Scientific model 210 VGP using spectrophotometry techniques. The highest mean concentration of Zn recorded in the sediment at the Motor Park Area was 0.55 mg/kg while the lowest value of 0.004 mg/kg was recorded for Cr at the Motor Park Area. The highest mean concentration of Mn recorded in the water was 0.375 mg/l at New Bridge Site while the lowest value of 0.00 mg/l was recorded for Cu. Values for Cu, Cd, Cr. Cu were generally low throughout the study period. There was no significant difference (p&gt;0.005) in Zn concentrations in sediment at the sampled locations (Motor Park Area and New Bridge Site) throughout the study periods. However, Cr, Cd and Pb show variations (p&lt;0.005) at the sampled locations. The concentration of Mn (0.375 mg/l) was not significantly different (p&gt;0.05) from Mn (0.325 mg/l) in water between the two location, Pb value (0.343 mg/l) of water in December at the New Bridge Site exceeded the WHO recommended safe limit. However, all other metals were within the WHO and FMENV safe limit for portable drinking water. Since Pb value (0.343 mg/l) exceeded the WHO and FMENV safe limit for December. It shows that there is need for continuous monitoring of Lower River Benue waters at Ibi, Taraba State.

A survey on heavy metal content in seawater and sediment was conducted in Jakarta Bay in May and October 2004. There is indication of significant presence of heavy metal in sediment. The contents of heavy metals in sediment at the western part of Jakarta Bay varied as follows: Pb = 10.67-35.19 ppm, Cd = 0.04-0.30 ppm, Cu = 7.41-74.70 ppm, Zn = 76.99-497.53 ppm and Ni = 4.58-18.75 ppm. At the central part of Jakarta Bay, they varied as Pb = 6.69-64.44 ppm, Cd = 0.01-0.442 ppm, Cu = 1.19-40.60 ppm, Zn = 53.87-275.68 ppm and Ni = 4.09-11.88 ppm and at the eastern of Jakarta Bay, Pb content varied between 3.64 and 43.97 ppm, Cd = &lt;0.001-0.320 ppm, Cu = 0.82-36.47 ppm, Zn = 78.27-230.68 ppm and Ni = 4.58-11.02 ppm. The concentration of Pb in May and of Cu in Octobei 2004 were found higher near the coast and decreases towards the open sea, which is commonly found in front of estuary such Angke and Cengkareng Drain. The concentration of Cd in Jakarta Bay was constant at all stations and does not show any correlation with the distance of station and estuary. Heavy metals content in sediment was high in Jakarta Bay.

Heavy metal removal is a worldwide problem in the field of sludge treatment. Based on the principle of centrifugation, a new method for reducing heavy metal content in river sediment is proposed in this paper. The implementation process is: (1) adding water to the original sediment and thoroughly mixing to obtain a rinse sediment, which is centrifuged by the centrifuge and obtain the dry sediment; (2) adding water to the primary dry sludge and mixing thoroughly to obtain the secondary leaching sediment, which is centrifuged in a centrifuge to obtain the secondary dry sediment. And so on, until the criteria for design requirement is met. Through four relative centrifugal forces and two centrifugal separation experiments, primary and secondary dry sediment of a certain sediment under four different relative centrifugal forces were obtained. ICP-MS test results show that the dry sediment obtained in the experiment condition with the relative centrifugal force is 100g (where g is the gravitational acceleration) and the number of rinses is 1. The content of heavy metals Cd and Ni that exceeds the original standard content has decreased significantly and meets the technical requirements for green metal planting soil heavy metal content level IV standards, removal rates are 46.6% and 20.9%, respectively; the content of other heavy metals that did not exceed the standard also decreased significantly. The method in this paper has many advantages include of good removal efficiency, no secondary pollution, especially new pollutions couldn't be introduced or generated.

Heavy metal concentrations in surface waters of Hurghada and environs, Red Sea Coast, Egypt, and their correlation with sediment distribution