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Heavy metals

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Articles 1 - 26 of 26

Full-Text Articles in Toxicology

Evaluation Of Heavy Metal And Health Risks Of Well Water In Abobo, Osara And Osaragada Communities In Kogi State, North-Central, Nigeria, Muhammed Haruna Isah, Blessing Ahmed, Dauda Tanko, Adang Kombe Lucas Jun 2026

Evaluation Of Heavy Metal And Health Risks Of Well Water In Abobo, Osara And Osaragada Communities In Kogi State, North-Central, Nigeria, Muhammed Haruna Isah, Blessing Ahmed, Dauda Tanko, Adang Kombe Lucas

Journal of Bioresource Management

Human health may be at risk if drinking water contains excessive amounts of heavy metals (HMs). To determine risks related to heavy metals, fifteen water samples were taken every month between July and September, 2024 from the communities of Abobo (Site A), Osara (Site B) and Osaragada (Site C) close to Confluence University of Science and Technology, Osara. These samples were tested for ten HMs (Cu, Fe, Ni, Zn, Co, Cd, As, Cr, Hg, Pb) with the aid of Atomic Absorption Spectroscopy. The average concentration ranges as follows: Fe (0.378-0.511 mg/l), Cu (1.643-1.720 mg/l), Ni (0.31-0.556 mg/l), Zn (0.17-0.271 mg/l), …


Evaluating Willow Establishment With Biochar For Remediation Of Mine Waste Soils: Amendment Ph Determines Plant Biomass And Metal Mobility, Madeline R. Webb Jan 2026

Evaluating Willow Establishment With Biochar For Remediation Of Mine Waste Soils: Amendment Ph Determines Plant Biomass And Metal Mobility, Madeline R. Webb

Dissertations, Master's Theses and Master's Reports

Heavy metal contaminated mine tailings (“stamp sands”) from historic copper mining inhibit plant establishment and contribute to ongoing metal contamination. Biochar amendments may enhance plant growth and reduce metal mobility in highly permeable mine waste soils, but the efficacies of different application methods or biochar sources and composition are uncertain. We evaluated different biochar sources (neutral or alkaline pH) and application methods (either mixed or layered) for planted willow growth, moisture retention, and metal mobility. A 10-week growth chamber experiment assessed plant performance, heavy metal content and heavy metal mobility in soil leachates and plant tissues. Biochar pH was the …


Evaluation Of The Water Quality And Distribution Of Heavy Metals In The Gomti River Flowing Through The Urban Region Of Lucknow, India, Neha Gondial, Sandhya Bharti Sep 2024

Evaluation Of The Water Quality And Distribution Of Heavy Metals In The Gomti River Flowing Through The Urban Region Of Lucknow, India, Neha Gondial, Sandhya Bharti

Makara Journal of Science

The physicochemical properties and heavy metals contents of the Gomti River water (GRW) samples collected from five selected sites covering a stretch of ~31 km in Lucknow, Uttar Pradesh, India were ascertained. The sites were Ghaila Pul, Mehndi Ghat, Shaheed Smarak, Kukrail Junction, and Bande Dam, represented as S1, S2, S3, S4, and S5, respectively, following from upstream to downstream. S1 was considered as a reference site. The values of pH, temperature, total dissolved solids (TDS), electrical conductivity (EC), turbidity, dissolved oxygen (DO), biochemical oxygen demand (BOD), total hardness (TH), total chloride (TC), total alkalinity (TA), total acidity (TAC), total …


Dangerous Dyes: The Poison Book Project At Lipscomb University, Michaela Rutledge, Jan Cohu Apr 2024

Dangerous Dyes: The Poison Book Project At Lipscomb University, Michaela Rutledge, Jan Cohu

Faculty Works

Last year, the Winterthur Library began a worldwide effort to identify 19th century books that have covers dyed with toxic heavy metals, such as arsenic and chromium, which they called the Poison Book Project. Lipscomb University joined in the Poison Book Project, looking for books dyed with dangerous chemicals. The library collaborated with the University's Chemistry department for the testing of suspected books. We will give results, recommendations, and resources for other libraries.


Heavy Metals Analysis And Physicochemical Characterization Of Groundwater At A Battery Recycling Site In South-Western Nigeria, Adeniyi T. Adeleke, Rasaki K. Odunaike, Shamsideen K. Alausa, Idris O. Olayiwola, Adetoro T. Talabi, Qasim A. Adeniji, Adejumobi C. Adeniyi Jan 2024

Heavy Metals Analysis And Physicochemical Characterization Of Groundwater At A Battery Recycling Site In South-Western Nigeria, Adeniyi T. Adeleke, Rasaki K. Odunaike, Shamsideen K. Alausa, Idris O. Olayiwola, Adetoro T. Talabi, Qasim A. Adeniji, Adejumobi C. Adeniyi

Tanzania Journal of Science

Indiscriminate dumping of battery waste is a huge issue that endangers human health and the environment. This study aimed at analysing the health impacts of exposure to pollution from spent battery recycling in Ogun State, which houses a diverse range of battery recycling industries. At this study site, forty water samples were studied over the Wet and Dry seasons to assess the impact of battery recycling waste on groundwater. Except for the TSS, the physiochemical parameters of the groundwater vary with season and are within the permissible limits. The electrical conductivity (EC), turbidity, Phosphorus, Biochemical oxygen demand (BOD), Dissolve oxygen …


Potential Of Constructed Wetlands For The Treatment Of Heavy Metals From Wastewater, Hasnain Raza, Qurat Ul Ain, Haseena Bibi, Tehmina Bibi, Huda Bilal Mar 2023

Potential Of Constructed Wetlands For The Treatment Of Heavy Metals From Wastewater, Hasnain Raza, Qurat Ul Ain, Haseena Bibi, Tehmina Bibi, Huda Bilal

Journal of Bioresource Management

Overpopulation, urbanization, and economic race increase the pressure on freshwater resources resulting in water scarcity challenges around the globe. Moreover, the generation of wastewater is also enhancing the scarcity threats for freshwater resources. Water scarcity issues forced the policymaker, thinker, scientist, and researcher to think about non-conventional water resources to cope with the increasing demands. This wastewater recycling and treatment play an evident role to fulfill the growing demand for freshwater in socioeconomic sectors especially, for agriculture, due to its 70 % dependency on freshwater resources. Different wastewater treatment methods along with merits and demerits are in practice for the …


Telomeres: A Tool To Assess The Impacts Of Mining Contaminants On Riparian Songbirds, Lillian Krach, Bridger Creel, Megan Fylling, Zac Cheviron, Creagh Breuner Jan 2023

Telomeres: A Tool To Assess The Impacts Of Mining Contaminants On Riparian Songbirds, Lillian Krach, Bridger Creel, Megan Fylling, Zac Cheviron, Creagh Breuner

Undergraduate Theses, Professional Papers, and Capstone Artifacts

Mining has left massive environmental and physical scars across the landscape. Aquatic and riparian landscapes in particular have been significantly impacted by traditional mining practices. Waste products left over from hard-rock mining leech heavy metals onto the landscape and these metals spread from headwater streams to major waterways (Lottermoser 2010). Heavy metals have been shown to cause physiological stress and challenges to organisms depending on the metal and the concentration (Baos et al. 2019, Boyd & Rajakaruna 2013). While some mining-impaired areas have undergone restoration efforts, is it enough? Typical restoration methods replace the contaminated floodplain, but not the riverbed …


Assessment Of Soil, Water Contamination And Land Cover Changes In The Urban And Suburban Watersheds Of Houston, Texas, Felica Rena Davis May 2022

Assessment Of Soil, Water Contamination And Land Cover Changes In The Urban And Suburban Watersheds Of Houston, Texas, Felica Rena Davis

Dissertations (2016-Present)

Intense urbanization and increased anthropogenic activity are two important factors contributing to the decline of soil and water quality in Houston watersheds, which poses a great environmental and human health risks. This study, therefore, was designed to: 1) determine nutrient and metal concentrations in soil and water samples along Carpenters Bayou (CaB), Cedar Bayou (CB), Sims Bayou (SB), Spring Creek Bayou (SC) and Vince Bayou (VB), 2) analyze land cover changes in watersheds using Landsat image analysis and 3) evaluate socio-economic characteristics and human health risks for each watershed. Soil and water samples were collected from three different locations with …


Behavioral And Physiological Effects Of Heavy Metals On Fish: A Review And Preliminary Results, Diana V. Morales Mar 2022

Behavioral And Physiological Effects Of Heavy Metals On Fish: A Review And Preliminary Results, Diana V. Morales

Theses and Dissertations

Pollution, specifically heavy metal pollution, in various bodies of water has been a significant issue for decades. Research has been conducted on heavy metals and their effects on the environment, larger fish species, and humans since the 1970s (Skidmore, 1964; Adeniyi et al., 2007; Adeosun et al., 2015; Bawuro et al., 2018). It is known that zinc is a neurotoxin in some species and causes harm to the environment. It is also known that it causes harm to people if it is ingested or if they are exposed to it for long periods of time (Mahurpawar, 2015; Mizuno and Kawahara, …


Heavy Metal Contamination And Potential Ecological Risks In Surface Sediments Along Dar Es Salaam Harbour Channel, Benard Mwakisunga, Harishchandra B. Pratap, John F. Machiwa, Flora Stephano Dec 2021

Heavy Metal Contamination And Potential Ecological Risks In Surface Sediments Along Dar Es Salaam Harbour Channel, Benard Mwakisunga, Harishchandra B. Pratap, John F. Machiwa, Flora Stephano

Tanzania Journal of Science

Investigation of heavy metal contamination along Dar es Salaam harbour channel was carried out in order to determine their current concentrations, sources and potential ecological risks to benthic biota. Sampling was carried out from January to May 2019 and samples analysed using ICP-OES and C-H-N-S analyser. Analysis of heavy metal relationships showed that, Cu, Zn, Cr, As, Ni, Co, Fe, Cd had strong relationships with each other, while Pb only related to Zn. Principal component analysis partitioned metals into two groups; PC1: Ni, Cr, Fe, Co, As, Cu, Cd, and Zn explaining 73.6% variance and PC2: Pb, Zn, and Cd …


Investigation Of Toxic Chemicals In Plant-Based Milk Alternatives, Chukwunonso A. Anakwue Dec 2021

Investigation Of Toxic Chemicals In Plant-Based Milk Alternatives, Chukwunonso A. Anakwue

Dissertations (2016-Present)

Milk is a dietary component consumed all over the world and is known to be essential for development in children. Despite all the nutritional advantages associated with milk consumption, several issues like lactose intolerance, and high lipid content, etc., negatively affects the perception of cow milk consumption, and has grown into general health concerns. Issues with cow milk consumption drove for a healthier alternative and this led to plant-based milk alternatives (PBMA). Several studies have linked consumption of these PBMAs with other negative effects such as: allergy, poor nutrient profile and the presence of other foreign chemicals. This study’s main …


Determination Of Metals And Microplastics In Sediment From Oyster Reefs In The Mississippi Sound, Shelby Goza May 2021

Determination Of Metals And Microplastics In Sediment From Oyster Reefs In The Mississippi Sound, Shelby Goza

Honors Theses

This research centers on the determination of metals (Cd, Pb, V, Cr, Mn, Fe, Co, Ni, Cu) and microplastics (MPs) in marine sediment from oyster reefs in the Mississippi Sound Estuary. Oysters (Crassostrea virginica) are a vital part of the Gulf Coast economy, but their population has dramatically declined in recent years due to multiple stressors, including oil spills and fluctuations in salinity from flooding. Increasingly frequent flooding events also introduce high loads of MPs and sediments containing heavy metals from the Mississippi River. These pollutants can have deleterious effects on oyster biology; however, they have not been adequately …


Levels Of Heavy Metals In Selected Facial Cosmetics Marketed In Dar Es Salaam, Tanzania, Joseph Yoeza Naimani Philip, Silvia John, Othman Chande Othman Jul 2018

Levels Of Heavy Metals In Selected Facial Cosmetics Marketed In Dar Es Salaam, Tanzania, Joseph Yoeza Naimani Philip, Silvia John, Othman Chande Othman

Tanzania Journal of Science

The aim of this study was to determine the levels of heavy metals: lead, cadmium, copper, zinc, arsenic and mercury in facial cosmetics (lipstick, lip glossy, facial powder, foundation, eyeliner, eye shadow and mascara) which were purchased randomly in Dar es Salaam, Tanzania. The levels of lead, cadmium, copper and zinc were determined using Atomic Absorption Spectrometry (AAS). The levels of arsenic were determined using Hydride Generation Atomic Absorption Spectrometry (HGAAS), and levels of mercury were determined using Cold Vapour Atomic Absorption Spectrometry. Prior to determination of the concentration of heavy metals, the samples were acid digested. The average order …


Levels Of Heavy Metals In Deposited Dust And Soil From Selected Primary Schools In Dar Es Salaam, Joseph Yoeza Naimani Philip, Eliamini Ismail Mkenga, Othman Chande Othman Jul 2018

Levels Of Heavy Metals In Deposited Dust And Soil From Selected Primary Schools In Dar Es Salaam, Joseph Yoeza Naimani Philip, Eliamini Ismail Mkenga, Othman Chande Othman

Tanzania Journal of Science

The objective of this study was to examine the levels of heavy metals, lead, manganese, nickel, copper, chromium and cadmium in standard one and kindergarten classroom dusts and playing ground soils from selected primary schools along Morogoro road highway (Kimara, Mbezi, Kibamba and Kiluvya primary schools) and away from Morogoro road highway (Makabe, Msumi and Mbopo primary schools) as well as in the Dar es Salaam city center (Uhuru, Mzimuni, Dr. Omari Ali Juma, Manzese and Ubungo National House primary schools), Tanzania. The samples were acid digested and the supernatant analyzed using inductively coupled plasma optical emission spectrometer (ICP-OES). The …


Levels Of Heavy Metals In Drinking Water, Cosmetics And Fruit Juices From Selected Areas In Dar Es Salaam, Tanzania, John Am Mahugija May 2018

Levels Of Heavy Metals In Drinking Water, Cosmetics And Fruit Juices From Selected Areas In Dar Es Salaam, Tanzania, John Am Mahugija

Tanzania Journal of Science

Heavy metals were determined in samples of drinking water, cosmetics (nail polish, lip glosses and hair dye) and fresh fruit juices in Dar es Salaam. The samples were analyzed using Atomic Absorption Spectrometry (AAS) after digestion with concentrated acids, filtration and dilution. Lead, zinc and iron were detected in the water samples and the concentration ranges were below detection limit (BDL) to 0.114, 0.01 to 1.47 and 0.027 to 0.39 mg/L, respectively, whereas cadmium was not detected. The concentrations of lead in 70.83% of the samples exceeded the WHO permissible limit, implying that the water in most of the areas …


Status Of Selected Heavy Metals Dispersion From Top Soil In And Around Automobile Workshop Areas In Zanzibar Municipality, Tanzania, John Am Mahugija, Hawa M Sheikh May 2018

Status Of Selected Heavy Metals Dispersion From Top Soil In And Around Automobile Workshop Areas In Zanzibar Municipality, Tanzania, John Am Mahugija, Hawa M Sheikh

Tanzania Journal of Science

The distributions of selected heavy metals in top soil in areas with and without automobile workshops in Zanzibar municipality were investigated. Sampling was done during dry and rainy seasons. The samples were digested with aqua regia (HCl and HNO3, 3:1) and analysed by Atomic Absorption Spectrophotometry. The concentrations of zinc, copper and lead in the samples ranged 0.27–419.2, 0.10–167 and 0.02–271 mg/kg dry weight, respectively. The concentrations were higher in areas with automobile workshops than those without. The concentrations of the heavy metals were highest at point sources and decreased with increase in distance during the dry season. The concentrations …


Assessment Of Heavy Metal And Radioactivity Levels In Spinach (Spinacia Oleracea) Grown At Bahi Wetlands In Dodoma Region, Najat K. Mohammed, Boniface Haule May 2018

Assessment Of Heavy Metal And Radioactivity Levels In Spinach (Spinacia Oleracea) Grown At Bahi Wetlands In Dodoma Region, Najat K. Mohammed, Boniface Haule

Tanzania Journal of Science

This study reports on the levels of heavy metals and radionuclides in Spinach (Spinacia oleracea) grown in Bahi wetlands in Dodoma Region. The farm soil in Bahi wetland has been reported to contain elevated concentrations of 238U, 232Th and 40K due to the existence of shallow uranium deposit in the area. In this study, spinach (Spinacia oleracea) grown in three zones of Bahi district were analyzed for heavy metals and radioactivity associated with the uranium deposit in the area. The concentrations of elements were determined by Energy Dispersive X-ray Analysis (EDXRF) of Tanzania Atomic Energy Commission, Arusha. The activities of …


An Ecotoxicological Survey Of Tributaries Of The Selenge River, Mongolia, August 2010, Viktor T. Komov, Ch. Javzan, William G. Brumbaugh Jan 2016

An Ecotoxicological Survey Of Tributaries Of The Selenge River, Mongolia, August 2010, Viktor T. Komov, Ch. Javzan, William G. Brumbaugh

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

The biodiversity of the Selenga river basin and the receiving waters of the lake Baikal, are among the greatest in the world with over 1,700 known endemic species of plants and animals. Mining activities along the Selenga river and its tributaries pose a major threat of chemical contamination, potentially reducing habitat quality and suitability for aquatic species. Moreover, the Selenga river serves as a major water source for the lake Baikal. Little information exists on the chemical contaminant concentrations in the Selenga river basin. Thus, the objectives of our study were to evaluate the concentrations of metals in soil, sediment, …


Heavy Metal Content In Some Commonly Consumed Vegetables From Kariakoo Market, Dar Es Salaam, Tanzania, Eb Mubofu Dec 2012

Heavy Metal Content In Some Commonly Consumed Vegetables From Kariakoo Market, Dar Es Salaam, Tanzania, Eb Mubofu

Tanzania Journal of Science

This work reports on the levels of cadmium, lead, copper, manganese and zinc in 174 samples from eight varieties of green vegetables (amaranth, Chinese cabbage, cowpea leaves, green pepper, leafy cabbage, lettuce, okra and pumpkin leaf) commonly grown in Dar es Salaam and marketed at Kariakoo, Tanzania. The amount of cadmium and lead ranged between 3-42 and 11-60 μg/kg respectively. The amount of copper, manganese and zinc ranged between 0.35 - 2.12, 1.01 - 7.57, and 1.19 - 6.33 μg/kg respectively. On average consumption pattern, the contribution of these vegetables to the recommended daily intakes (RDI) for cadmium and lead …


Classification Of Plants According To Their Heavy Metal Content Around North Mara Gold Mine, Tanzania: Implication For Phytoremediation, N. Mganga, Mlk Manoko, Z. K. Rulangaranga Dec 2011

Classification Of Plants According To Their Heavy Metal Content Around North Mara Gold Mine, Tanzania: Implication For Phytoremediation, N. Mganga, Mlk Manoko, Z. K. Rulangaranga

Tanzania Journal of Science

Plants like other living organisms respond differently under different environmental conditions. An elevated level of heavy metals is one of the stresses which results into three classes of plants depending on their heavy metal content. The classes of plant species according to their accumulated heavy metals around North Mara Gold Mine were not known. To study such classes, a line transect of 700m long was established opposite the gold mine wastes. A total of eight sampling points were systematically established each after every 100m in that transect. Fifteen plant species were sampled; at least one species per sampling point. Approximately …


Monitoring Of Heavy Metal Loading Into The Wetlands South Of Lake Victoria Basin, Nothern Tanzania, M K D Mutakyahwa, J R Ikingura, G Y S Mtui Jul 2009

Monitoring Of Heavy Metal Loading Into The Wetlands South Of Lake Victoria Basin, Nothern Tanzania, M K D Mutakyahwa, J R Ikingura, G Y S Mtui

Tanzania Journal of Science

The paper discusses sources, concentrations and physicochemical parameters of heavy metals of environmental concern in the wetlands of Lake Victoria basin in Tanzania. The metals investigated include copper (Cu), lead (Pb), zinc (Zn), cadmium (Cd), chromium (Cr), nickel (Ni), arsenic (As), manganese (Mn), cobalt (Co) and mercury (Hg). These metals are released into the wetlands via weathering and erosion of rock formations, mining operations and industrial activities, discharge of municipal and domestic waste, and use of agrochemicals. The levels of these heavy metals in soil, sediment, water, and biota differ. Wetlands impacted by gold mining activities in the South Lake …


Heavy Metal Contamination Of Mangrove Sediments And The Associated Biota In Dar Es Salaam, Tanzania, Sd Mremi, Jf Machiwa Jul 2003

Heavy Metal Contamination Of Mangrove Sediments And The Associated Biota In Dar Es Salaam, Tanzania, Sd Mremi, Jf Machiwa

Tanzania Journal of Science

Mangrove wetlands are efficient in trapping pollutants that may have detrimental effects on mangrove dependent food chains. Mangrove ecosystems that are within urban areas are likely to suffer more from chemical pollution than those in rural areas. Heavy metals in mangrove plant parts, sediments and crabs from mbweni, msimbazi and mtoni mangrove ecosystems in Dar es salaam were analysed using an atomic absorption spectrophotometer, in order to assess the impact of heavy metal pollution on mangrove biota. Sediment samples from msimbazi and mtoni mangrove areas which are located within the city, had higher levels of pb, zn and cu than …


Optimization Of Edxrf For The Study Of Heavy Metal Pollution Of Lake Victoria, Nk Mahommed, In Makundi Nov 2002

Optimization Of Edxrf For The Study Of Heavy Metal Pollution Of Lake Victoria, Nk Mahommed, In Makundi

Tanzania Journal of Science

This study reports on the optimisation and calibration of the Energy Dispersive X-ray Fluorescence (EDXRF) spectrometer installed in the Department of Physics, University of Dar es Salaam. The spectrometer was subsequently utilized to determine concentrations of heavy metals in water hyacinth (Eichhornia crassipes (Mart) Solms.) found growing along the shore of Lake Victoria. The optimal conditions and detection limits were determined experimentally by variation of the excitation parameters. The study found that the use of a collimator with two apertures of diameter 4 mm each placed 8 mm apart and made of materials that do not interfere with elements to …


Assessment Of Heavy Metal Pollution In The Lupa Gold Field, Sw Tanzania, S. R. Mnali Dec 2001

Assessment Of Heavy Metal Pollution In The Lupa Gold Field, Sw Tanzania, S. R. Mnali

Tanzania Journal of Science

The concentrations of AS, Cd, Cr, Cu, Hg and Pb were determined in water, stream sediments, soil, and mine tailings from Lupa Gold Field (LGF), SW Tanzania, in order to assess their pollution levels. As, Cd and Cr were determined by automated Graphite Furnace Absorption Spectrophotometry. Cu and Pb were analysed by Air-Acetylene Flame, while Hg was analysed by Cold Vapour Atomic Absorption Spectrophotometry. The mean concentrations obtained were: As: 0.44 ppb (water), 1.2 ppm (sediments), 0.44 ppm (soil) and 5.2 ppm (tailings); Cd: 0.03 ppb (water), 0.03 ppm (sediments), 0.03 ppm (soil) and 0.50 ppm (tailings); Cr: 1.4 ppb …


Heavy Metals In Green Vegetables And Soils From Vegetable Gardens In Dar Es Salaam, Tanzania, O C Othman Jul 2001

Heavy Metals In Green Vegetables And Soils From Vegetable Gardens In Dar Es Salaam, Tanzania, O C Othman

Tanzania Journal of Science

Edible portions of five varieties of green vegetables, namely amaranth, chinese cabbage, cowpea leaves, leafy cabbage and pumpkin leaves, collected from several areas in Dar es Salaam, were analyzed for lead, cadmium, chromium, zinc, nickel and copper. Except for zinc, the levels of heavy metals in the vegetables grown at Tabata area were much higher than in the vegetables from Ukonga and Kiwalani. Amaranth and pumpkin leaves had more than 60% higher content of heavy metals, especially copper, chromium and lead, than the other vegetables. All vegetables from Tabata, Buguruni and Sinza had lead-levels higher then the FAO/WHO recommended permissible …


Heavy Metals And Organic Pollutants In Sediments Of Dar Es Salaam Harbour Prior To Dredging In 1999, J F Machiwa Dec 2000

Heavy Metals And Organic Pollutants In Sediments Of Dar Es Salaam Harbour Prior To Dredging In 1999, J F Machiwa

Tanzania Journal of Science

Heavy metals and organic contaminants were analysed in the sediments of the inner area of the Dar es Salaam harbour. Complementary analytical parameters, such as, the organic carbon content and the silt/clay fraction of the sediments showed good positive correlation (r = 0.64). Stations that had high content of fine grain material in the sediment also indicated relatively high level of organic carbon and pollutants. The Florida criteria (MacDonald 1993) for assessment of pollution of tropical marine sediments was adopted in oredr to evaluate the extent of pollution in Dar es Salaam harbour sediments. The Florida criteria is one of …