Maximum Admissible Concentration Research Articles

Spatial variability and risk assessment of potentially toxic elements in the effluent of Kumasi Abattoir [sbnd] Ghana

Hypothesis-driven experiments have been conducted to explore the spatial variability and potential ecological risk indices (RIs) of potentially toxic elements (PTEs) in untreated in situ effluent continuously discharged downstream by the Kumasi Abattoir Ghana (KAG). The study focused on seven PTEs nickel (Ni), lead (Pb), cadmium (Cd), manganese (Mn), zinc (Zn), copper (Cu), and iron (Fe), based on these hypotheses: (i) Variations in PTE levels may be significant in the effluent; (ii) Comparative RI assessments based on the three background values natural background values (NBVs) for freshwater, maximum admissible concentrations (MACs), and reference values (RVs) provide objective evaluations; and (iii) PTEs’ cluster distances are linked to RIs. Effluent samples were randomly collected in quintuplicates from the drainage receptacle and analyzed using standard methods. The spatial variability of PTEs was investigated using divisive hierarchical cluster analysis (DHCA). The RIs and their uncertainties were computed using Hakanson's equations and standard deviation (SD). PTE dispersion was analyzed using the coefficient of variation (CV). Analysis of variance (ANOVA) was employed to test for the significance of hypotheses 1 and 2, complemented by Scheffé's post-hoc test where significance was detected. Hypothesis 3 was investigated by analyzing PTE cluster distances and RIs based on Pearson's correlation metric. The DHCA produced two clusters Cd–Cu–Mn–Ni and Zn-(Fe)-Pb. The CVs (< 50 %) indicated medium variability, relatively uniform spatial distributions, and minimal fluctuations. High to very high RIs ± SDs obtained were 300 ± 57.5 (MACs), 2900 ± 500 (RVs), and 7666 ± 2980 (NBVs). The ANOVA yielded significant results for both hypotheses, while moderate to high correlations were obtained for the third hypothesis. While RIs provided compelling evidence of inimical effluent, the study highlights the influence of background values on RIs. It further suggests that the PTE cluster distances may be used as surrogates for the RIs.

Initial assessment of the chemical state of the water in the upper part of Iskar River

The ecological status of the water in the Iskar River basin is of utmost importance because it provides more than 70% of Sofia’s drinking water. It is considered that the major point source of pollution in the upper Iskar aquatic ecosystems is the discharge from the wastewater treatment plant (WWTP) in the town of Samokov. This study aims to assess the environmental impact of treated effluent discharge from the WWTP - Samokov in the upper part of the Iskar River. Autumn and spring sampling was carried out (November 2020, March 2021, November 2021 and March 2022) at four sampling points upstream and downstream of the WWTP - Samokov and from a discharge of a local WWTP in the village of Belchin. The contents of macro-, micro- and trace elements, as well as inorganic anions were determined and compared with the requirements of Bulgarian legislation. Тhe concentrations of the macroelements Na, K, Ca, Mg, P, S and Si were relatively stable in the studied sampling points and seasons. The concentrations of the main part of the regulated microelements were below the maximum admissible concentrations (MACs). Seasonal exceedance of the MACs was established for Al, Fe, Hg before and after the discharge, which is an indication of diffuse pollution. The presence of Cl-, NO3- and SO42- was found, and the highest concentrations were determined at the discharge, but were below the MACs according to the requirements of Bulgarian legislation.

Shelf life estimation of refrigerated vacuum packed beef accounting for uncertainty

This study estimates the shelf life of vacuum packed beef meat (three muscles: striploin (longissimus thoracis et lumborum, LTL), tenderloin (psoas major, PM) and outside chuck (trapezius thoracis, TT)) at refrigeration temperatures (0 °C–10 °C) based on modelling the growth of two relevant groups of spoilage microorganisms: lactic acid bacteria (LAB) and Enterobacteriaceae. The growth models were developed combining a two-step and a one-step approach. The primary modelling was used to identify the parameters affecting the growth kinetics, guiding the definition of secondary growth models. For LAB, the secondary model included the effect of temperature and initial pH on the specific growth rate. On the other hand, the model for Enterobacteriaceae incorporated the effect of temperature on the specific growth rate and the lag phase; as well as the effect of the initial pH on the specific growth rate, the lag phase and the initial microbial count. We did not observe any significant effect of the type of muscle on the growth kinetics. Once the equations were defined, the models were fitted to the complete dataset using a one-step approach. Model validation was carried out by cross-validation, mitigating the impact of an arbitrary division between training and validation sets. The models were used to estimate the shelf life of the product, based on the maximum admissible microbial concentration (7 log CFU/g for LAB, 5 log CFU/g for Enterobacteriaceae). Although LAB was the dominant microbiota, in several cases, both LAB and Enterobacteriaceae reached the critical concentration practically at the same time. Furthermore, in some scenarios, the end of shelf life would be determined by Enterobacteriaceae, pointing at the potential importance of non-dominant microorganisms for product spoilage. These results can aid in the implementation of effective control measures in the meat processing industry.

Effect of Aqueous Extract of Ichthyotoxic Plant Bridelia micrantha (Hochst) (Baill) on Haematology, Histopathology and Carcass Characteristics of African Catfish (Clarias gariepinus) (BURCHELL, 1822) Juvenile

The Bridelia micrantha (Hochst.) (Phyllanthaceae) is an ichthyotoxic plant used in catching fish in Nigeria. The toxicity of aqueous extract of B. micrantha on Clarias gariepinus was investigated under statics bioassay conditions. The concentrations of the leaves extract used were 0.00, 0.10, 0.20, 0.30, 0.40, 0.50 and 0.0.60ml/l. The 24hrs, 36hrs, 48hrs, 72hrs, and 96hrs LC50 were 0.40mg/l, 0.30mg/l, 0.26mg/l, 0.22mg/l and 0.21mg/l respectively, with the range of maximum admissible concentration (MATC) were 0.004 – 0.04, 0.003 – 0.03, 0.0026 – 0.026, 0.0022 – 0.022, and 0.0021 – 0.021 respectively. The opercula ventilation and loss of reflex increased with an increase in the concentrations of the leaves extract at the end of 96-hour exposure period. Respiratory distress, loss of balance, settling at the bottom motionless and erratic swimming was observed before death during the exposure period. There was no significant difference in physicochemical parameters of test media (P&lt;0.05) before, during and after the experimental period. Total Dissolved Solids and Conductivity increased significantly (p&lt;0.05) with increase in extract concentration. Temperature had nonsignificant (p&lt;0.05) reduction at all extract concentrations. Blood analysis revealed significant (P&lt;0.05) reduction in the blood parameters (Haemoglobin, Packed Cell Volume, Red Blood Cells, White Blood Cells, Platelet, Mean Corpuscular Volume and Mean Corpuscular Haemoglobin) of exposed fish. There was severe reduction in Carcass/Proximate (Moisture, Crude Protein, Crude Lipid, Ash, NFE, and Energy) composition of Clarias gariepinus juvenile exposed to B. micrantha. Histopathological examinations of the test fish showed some pathological disruptions, such as skin layer with severe superficial spreading of melanoma, The liver cells revealed hepatic tissue with severe ground glass (GG) appearance of the cytoplasm and intra hepatic hemorrhage (IHH), The gill showed severe effect on the gill architecture with hypertrophy of the gill arch, gill filament and aggregate of inflammation (AI), while the kidney revealed severe degeneration of the renal tissue with severe intra renal necrosis (TN). The result of this study calls for the need to discourage the use of toxic plants for catching fish in Cross River and Nigeria water bodies.

ՍԻԼԻՑԻՈՒՄԻ ՀՆԱՐԱՎՈՐ ԲԱՐԵՆՊԱՍՏ ԱԶԴԵՑՈՒԹՅՈՒՆՆ ԱՌՈՂՋՈՒԹՅԱՆ ՎՐԱ

Silicon is one of the most common elements in the earth’s crust. It is always present in water and food in varying amounts. Higher amounts of Si are found in plant-based foods. About 20% of the total amount of silicon ingested with food and water comes with drinking water and drinks (including beer, which contains in average 20–25 mg/l of silicon)․ For higher animals and humans, silicon is generally not considered to be an essential nutrient. However, the importance of this element for human health is now supported by increasing research evidence. The biological role of silicon in human organism is still not clear, but it assumed to be necessary for processes of bone mineralization, collagen synthesis. It has a positive effect on the skin, hair, and nails, contributes to the prevention of atherosclerosis and Alzheimer disease. In the population of most Western countries, dietary Si intakes range from 20 to 50 mg/day. In addition to the beneficial effect of Si on health, questions regarding the adverse effect of this element on the body are also discussed in the literature. First of all, we are talking about the Russian authors’ researches in the field of drinking water hygiene. At present, the adequate and maximum admissible levels of Si consumption have not yet been established. Taking into account the results of research on humans and animals, some scientists have suggested a dietary intake of Si of about 25 mg/day. As for the standards of silicon content in drinking water, it is not regulated in the drinking water quality guidelines of the WHO and the European Union, as well as in the national normative documents of different countries. In the Russian Federation, as well as in the Republic of Armenia, in the hygienic requirements for water quality, Si is normalized according to the sanitary-toxicological index, with the value of the maximum admissible concentrations in drinking water amounting to 10 mg/l.

Influence of Moisture in Museum Rooms on the State of Microbial Contamination of the Air and Decoration Surfaces: The Example of a 17th Century Monument in the Museum of King John III’s Palace at Wilanow (Warsaw, Poland)

This article is a case study of museum premises at the Museum of King John III’s Palace at Wilanow (Warsaw, Poland), wetted as a result of a failure of the water supply system to the air conditioning unit located in the attic of the building. As a result of flooding, discoloration and cracks appeared on the plaster and stucco decoration of the ceiling, located mainly in the central part of the ceiling of the King’s Library. The paintings (plafonds) mounted on the ceiling of this room also became damp. The article analyzes the microbiological contamination of air and damp paintings in the context of promptly proceeding with the drying of damp building partitions. The obtained results of microbiological air pollution in the flooded rooms were significantly lower than the permissible values recommended by Interdepartmental Commission for Maximum Admissible Concentrations and Intensities for Agents Harmful to Health in the Working Environment. In the King’s Library, i.e., the room with the dampest plaster and stucco as a result of the accident, the concentration of mold spores in the air was only 15 cfu/m3. This means that the immediate commencement of intensive drying of the building partitions (walls, ceilings with wooden floors) brought very good results. The rapid reduction in the moisture of the building partitions contributed to the worsening conditions for the development of microorganisms, which can have an adverse effect on wooden building partitions, plaster, stucco, etc.

Dissipation of environmental DDT and its metabolites in selected rivers of south-western Kenya

Rivers are the main source of domestic and industrial water supplies in Kenya. In this study, water sampling was done at eight upstream sites in the Kuja River catchment, Kenya, between October 2016 and April 2017, specifically to test for residue levels of the organochlorine pesticide, dichlorodiphenyltrichloroethane (p,p′-DDT), and its degradation products, dichlorodiphenyldichloroethylene (p,p′-DDE) and dichlorodiphenyldichloroethane (p,p′-DDD). The analysis was performed with gas chromatography coupled with electron-capture detection in an autosampler. Concentrations of these residues in the surface water samples ranged from below detection limit (BDL) to 1.1113 μg l-1 in the wet season, and from BDL to 2.007 μg l-1 in the dry season. Overall, the highest mean residue concentration was for p,p′-DDT (0.9669 ± 0.2994 μg l-1). The lowest mean concentration in the dry season was that of p,p′-DDE (0.1824 ± 0.0964 μg l-1), and in the wet season it was p,p′-DDD (0.0610 ± 0.0038 μg l-1). From our results it is evident that DDT is still in use and detectable in the study area, though the mean levels detected were below the acceptable thresholds for natural water as suggested by the World Health Organization (WHO). Except for a slightly higher mean spatial distribution of the metabolite p,p′-DDT, the resides were recorded as below the maximum admissible concentrations of pesticide residues in drinking water, as set out in WHO guidelines and by Kenya’s National Environment Management Authority (NEMA). Monitoring organochlorine pesticide contamination levels in Kenya’s water resources should be scaled up to leverage potential for a sustainable blue economy and in safeguarding human and environmental health.

Impact of inorganic and organic pollutants from a Belgian wastewater treatment plant on adjacent surface and groundwaters

Under the pressure of global droughts and water shortage, it is essential to evolve toward a sustainable and robust water system. One possible avenue is the maximum reuse of treated wastewater, but the quality of which determines its reuse. Therefore, inorganic (Cd, Pb, Cr, Ni, Cu, and As) and organic (xenoestrogens and polycyclic aromatic contaminants, PACs) contaminants were monthly monitored in an effluent of the wastewater treatment plant (WWTP), the surrounding surface waters and the local groundwater in Belgium. Dissolved and particulate concentrations of inorganic contaminants in these water bodies were analyzed. In addition, Diffusive Gradients in Thin-films (DGT) was used in situ to obtain bioavailable metal fractions. In the WWTP effluent and surface waters, only Ni exceeds the Annual Average-Environmental Quality Standard (AA-EQS), while in the groundwater, dissolved As was the predominant element. Moreover, in the surface and effluent waters the highest lability degrees were observed for Cd and Ni. The concentrations of these metal species in the effluent water were lower than in the other water bodies. Micro-organic pollutants, xenoestrogens and PACs were analyzed by dual Estrogen and Aryl hydrocarbon Receptor - Chemical Activated LUciferase gene eXpression (ER & AhR-CALUX) assays. Since the annual averaged (AA) bioequivalent concentration of E2 (0.18 ng/L) is below the AA-EQS standard (0.4 ng/L), and the bioequivalent concentration of benzo[a]pyrene never exceeded the maximum admissible concentration (MAC), the reclamation and reuse of treated wastewater for groundwater replenishment and agricultural irrigation should pose no environmental problems, at least in a short-term.

Assessment of occupational exposure to elemental carbon in plants using diesel machinery and equipment

This paper presents and discusses the results of the determination of elemental carbon emitted in diesel engine exhaust into the air of workplaces where machines and equipment with diesel engines are used. In order to assess occupational exposure to elemental carbon (EC) as a marker of exhaust gases emitted by diesel engines, 51 ground-based workplaces where people who operate or maintain equipment with this type of engine work were measured. Measurements were also carried out at 9 workplaces in non-coal mines. For air sampling at workplaces of diesel exhaust emitting machines and equipment located on the surface, a cartridge sampler without an impactor with a quartz filter was used for elemental carbon determination, while for measurements in non-coal mines the Higgins-Dewell Cyclone FH022 respirable fraction sampler was used. The thermo-optical carbon analysis method using a flame ionisation detector was used to determine elemental carbon. Analysis of the results of the determined elemental carbon concentrations at workplaces located on the ground, i.e., in car repair shops, and in the steelworks where combustion forklifts are operated, showed that the highest concentrations of elemental carbon were determined at the old forklift workplaces in the steelworks. The determined EC concentrations at these workstations were 353 μg/m3 and 78 μg/m3, respectively. In the non-coal mines, elemental carbon concentrations were in the range of 7.5-50 μg/m3. Exposure assessment at the surveyed workplace in the steelworks showed the highest 7-fold exceedance of the maximum admissible concentration (MAC) at the position of the combustion forklift operator. At the other surveyed workplaces in the car repair shop the marked concentrations were in the range of 0.1-0.5 MAC or <0.1 MAC. In non-coal mines, the determined concentrations ranged 0.12-1 times the MAC. Med Pr. 2023;74(2):93-102.

Method for the determination of tetrachloromethane, trichloroethane, 1,1,2-trichloroethane, and tetrachloroethene in the air at workplaces

Chemical substances from the halogenated aliphatic hydrocarbons group are used in industry, e.g., as intermediates in syntheses, auxiliaries, solvents in degreasing processes, and laboratory tests. Due to their harmful effects on human health and the environment, their use is often banned or limited to certain industrial uses only. A sorbent tube containing 2 layers (100/50 mg) of coconut shell charcoal was used as a sampler for air sampling. Gas chromatography-mass spectrometry technique and the use of HP-5MS column (30 m × 0.25 mm × 0.25 μm), an oven temperature ramp program from 40°C to 250°C and selected ion monitoring mode were chosen for the determination. The established chromatographic conditions enable the simultaneous determination of tetrachloromethane, trichlorethane, 1,1,2-trichloroethane and tetrachloroethene in the concentration range 2-100 μg/ml. The average desorption coefficients obtained were: 0.97 for tetrachloromethane, 0.96 for trichloroethene, 0.96 for 1,1,2-trichloroethane and 0.96 for tetrachloroethene. The calculation of the substance concentration in the analyzed air requires the determination of the amount of substances trapped by the sorbent tube, the desorption coefficient and the air sample volume. Adequate dilution of the extract makes it possible to determine tetrachloromethane, trichloroethene, 1,1,2-trichloroethane and tetrachloroethene in ranges corresponding to 0.1-2 times the maximum admissible concentrations in the workplace air. This article discusses the issues occupational safety and health, which are the subject matter of health sciences and environmental engineering research. Med Pr. 2023;74(1):53-62.

Воздействие орошаемого свиноводческими стоками массива на поверхностные, грунтовые и подземные воды прилегающей территории

Purpose: to identify the impact of pig-breeding wastewater from the breeding-hybrid center (SGC) “Zadneprovsky”, Orsha district, Vitebsk region, on water bodies of the adjacent territory, namely on surface, ground and subsurface waters based on the results of many years of research, which gives an idea of the ecological state of the environment around large livestock complexes. Materials and methods: the influence of long-term irrigation with prepared pig wastewater has been edetermined based on studies of water quality samples from surface water sources near the complex, ground wells located at a distance of 800–1200 m from the area irrigated with wastewater, and from wells drilled to a depth of 80–230 m into the aquifer and located directly on the territory of the complex. Results. In the Krapivenka river, 500 m above the inflow of water from the Savishchino reservoir, ammonium nitrogen is found in an amount (mg per cubic dm) of 0.421 with a norm of 0.39, nitrite nitrogen – 0.025 with a maximum admissible concentration (MAC) of 0.024, phosphate phosphorus – 0.132 with a norm of 0.066 mg in cube dm. In the wells of the adjacent settlement of Krashino, located at a distance of 4600 m from the irrigation system of the Zadneprovsky SGC, excesses of MAC or nitrates were recorded. The nitrate content in well No. 1 was 1150 (mg per cubic dm), which is 25 times higher than the maximum admissible concentration. For wells No. 2 and 3, these values were 136 and 219, respectively, the excesses were 3 and 5 times. Exceeding the MAC for nutrients was not detected in subsurface water. Conclusions: pollution of surface waters located in close proximity to the pig-breeding complex is associated with violation of the technological regulations for storage and discharge of pig breeding wastewater. The increased content of nitrates in wells is due to their entry with groundwater, and pig waste does not have a significant impact on groundwater lying below the confining layer composed of clayey moraine deposits.

Risk Assessment of Potentially Toxic Elements in Agricultural Soils of Al-Ahsa Oasis, Saudi Arabia

Contamination of soil with potentially toxic elements (PTEs) is receiving great attention worldwide due to its apparent toxicity and hazards to local residents. The assessments of soil PTE distribution, sources, and environmental risks are, therefore, the first steps of high-efficiency pollutant degradation and sustainable utilization. The current study used a variety of contamination indicators and multivariate methods to evaluate the environmental risk of As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn in Al-Ahsa soils in eastern Saudi Arabia. For analysis, 30 surface soil samples were collected from palm fields irrigated with groundwater and treated sewage water. Landsat images of Al-Ahsa indicated an increase in the total vegetative area and the residential area, and a decrease in the bare land area from 1985 to 2021. The average concentrations of PTEs (mg/kg−1) were lower than the maximum admissible concentrations and had the following decreasing order: Zn (54.43) &gt; Cr (28.67) &gt; Ni (14.53) &gt; Cu (10.83) &gt; Pb (5.23) &gt; As (2.27) &gt; Hg (0.35) &gt; Cd (0.26). The enrichment factor (EF) findings confirmed that the Al-Ahsa soil is significantly enriched with Hg, moderately to severely enriched with As, and moderately enriched with Cd. The potential ecological risk index (RI) demonstrates a moderate ecological risk, with only certain parts presenting a high risk. The different PTE levels in agricultural soils may be caused partly by the various qualities of groundwater that originate from various aquifers and sewage-treated water. The results of a multivariate analysis showed that most of the anthropogenic sources of Hg, As, and Cd may come from using a lot of fertilizers and insecticides. Levels of the remaining PTEs indicated natural sources from earth crust materials.

Groundwater chemistry, pollution and health risk assessment for nitrogen compounds. A case study in a suburban region of Romania

As groundwater is used as a source of drinking water, monitoring its quality is essential due to possible adverse effects on human health. Nitrogen compounds (nitrates, nitrites, ammonia) within certain concentration limits are natural components of the nitrogen cycle. Due to anthropogenic activities, high concentrations of nitrogen compounds are released into groundwater. The aim of this study was to evaluate the chemistry of groundwater in a suburban area in northeastern Romania, the sources of pollution with nitrogen compounds (nitrates, nitrites, ammonium), and the non-carcinogenic risk to human health associated with consumption in different groups age (women, men, and children) in the investigated region. The results showed that the concentration of nitrogen compounds varies from 5.12 to 98.3 mg/L for nitrates, from 0.008 to 85.2 mg/L for ammonium, and from 0.001 to 1.12 mg/L for nitrites. The maximum admissible concentrations have been exceeding 25%, 40% and respectively 10% of the total analyzed samples Bivariate graphs and Principal Component Analysis (PCA) were used to identify potential sources of nitrate, nitrites, and ammonium pollution of groundwater in the study area. The non-carcinogenic risk assessment for water consumption showed a hazard index (HItotal) for nitrogen compounds in groundwater in the investigated region, which ranged from 0.037 to 2.856 for men, between 0.054 and 3.427 for women, respectively between 0.080 and 6.145, for children. Spatial distribution maps using the Inverse Distance Weighting technique presented the geographical areas with the probability of groundwater contamination with nitrate, nitrite, and ammonium and the areas that pose a risk to human health by consuming groundwater in the study area for the three groups: men, women and children.

LEGAL FEATURES OF BASIN-WIDE REGULATION OF POLLUTANTS DISCHARGES INTO SURFACE WATERS

The article examines the environmental and legal mechanism of the Ukrainian limitation regulation of pollutant discharges (RPD) into water bodies (WB). The central methodological link of RPD is the «Basin principle of determination of standards of maximum allowable pollutant discharge» (BPDSMAPD). This principle introduced by outdated regulatory &amp; legal and regulatory &amp; technical acts of last century. This basin principle (BP) based on the use of the assimilative possibility (AP) of WB for the environmental &amp; economic purposes of reducing the harmfulness of hazardous substances discharged into WB to the level of maximum admissible concentrations (MAC) in water for various purposes of water use. This RPD method does not meet the requirements for harmonization with modern EU water legislation. The terminological error in the name does not allow differentiate the concept of "basin management principle", which has its roots in EU water legislation, and Ukrainian concept BPDSMAPD. Instead, the term "determination of MAC standards for cascading discharge of P" was proposed. The environmental &amp; legal grounds, justification and consequences of the application of the BPDSMAPD, and requirements for the maximum permissible discharges (MPD) of P in Ukrainian environmental and water legislations identified. Under BP approach the AP phenomenon should be considered as a common beneficial quality of WB for the cascade of P discharges, which is subject to distribution among economic entities in case of special water use. It was determined that in fact the AC has a local (point) not a basin property and is not subject to division. In the environmental and water legislation of Ukraine as and EU, there is no concept of AC, and requirements for the use of AC are not established. Made conclusions that the "right to quota" of AP for water users, on which based the BP, does not exists, and the actual implementation of the BP leads to a violation of the basic legal right to use the same MPC within entire territory of Ukraine. The path to the legal regulation of the cascading discharge of P through the introduction of changes in the Ukrainian water legislation aimed at the organization of joint special water use is proposed.

Evaluation of sediment and water quality of Ismailia Canal for heavy metal contamination, Eastern Nile Delta, Egypt

Several environmental indicators were used to evaluate the water and sediment quality of Ismailia Canal for heavy metal contamination. The average concentrations of heavy metals in water and sediments (μg/L and μg/g) were Pb (1.36–31.78), Fe (0.95–5124), Ni (0.45–32.14), Cu (0.34–32.64), Zn (0.28–117.77), Co (0.078–29.40), and Mn (0.044–194.83), respectively. Based on heavy metal pollution index values, 75% of the sediment samples fell within low pollution, while water pollution index and water contamination degree revealed excellent and low contamination for all water samples, respectively. Single pollution indices of sediment indicated high contamination with Pb and considerable risk with Cd. The higher levels of metals in some samples might be originated mostly from anthropogenic sources related to industrial, agricultural, and urbanization activities along the investigated canal. However, Ismailia Canal sediments were unpolluted with metals, or no metal pollution and all average concentrations of the investigated heavy metals were less than the maximum admissible concentration of the world health organization.

Transpozycja dyrektywy 2019/1831/UE z dnia 24 października 2019 r. ustanawiającej piąty wykaz wskaźnikowych dopuszczalnych wartości narażenia zawodowego do prawa krajowego

The issue of the regulations amending the Regulation of the Minister of Family, Labour and Social Policy on the maximum admissible concentrations and intensities of agents harmful to health in the working environment resulted from the requirement to implement into national law the provisions of Commission Directive (EU) 2019/1831 of 24 October 2019 establishing a fifth list of indicative occupational exposure limit values pursuant to Council Directive 98/24/EC, and amending Commission Directive 2000/39/EC, the provisions of which Member States had to introduce by 20 May August 2021. The Regulation takes into account 3 motions submitted by the Interdepartmental Commission for Maximum Admissible Concentrations and Intensities for Agents Harmful to Health in the Working Environment to the minister of labour in the years 2017-2020. The Commission was appointed by the Regulation of the Prime Minister of December 15, 2008 (Journal of Laws of 2015, item 1772, with amendments), and its tasks include submitting to the minister of labour motions on the value of the maximum admissible concentrations and intensities for agents harmful to health in the working environment. Med Pr. 2022;73(1):43-50.

Determination of phenyl(2-naphthyl)amine concentrations in the working environment air using HPLC-FLD technique

Phenyl(2-naphthyl)amine (FNA) is a flammable solid with a characteristic odor. FNA is used, among others, in the production of paints and dyes, and as an antioxidant in rubber processing, lubricant for automobile engines, in brake fluids, oils, etc. In the European Union, FNA is classified as a category 2 carcinogen. In Poland, the value of the maximum admissible concentration (MAC) for FNA is 0.02 mg/m3. The aim of this study was to develop a new method for the determination of FNA, which will allow for the determination of this substance in the working environment within the concentration range of 0.1-2 of MAC value. The method is based on the retention of FNA on a cellulose filter, recovery of the substance with methanol and analysis of the solution thus obtained using a high-performance liquid chromatograph with a fluorescence detector. The developed method enables the determination of FNA in the concentration range 2-40 μg/m3. The limit of detection (LOD) is 0.23 ng/l and the limit of quantification (LOQ) is 0.69 ng/l. The method complies with the requirements of the European Standard PN-EN 482 and can be used to determine FNA concentrations in the workplaces air. Med Pr. 2022;73(1):25-31.

Level of Contamination of Fishponds Water in Pesticide Residues and Metallic Trace Elements (Pb, Cd, As, Hg): Case of Fishponds of ZEPREGUHE (Daloa, C&amp;amp;ocirc;te d’Ivoire)

Fishponds waters intended to satisfy the nutritional needs of the populations in terms of supply of fish resources are strongly and unfortunately exposed to the mobility and dispersion of metallic trace elements (TMEs) or to the persistence in the environment and in the form of pesticide residues from human activities. The objective of this work is to evaluate, on the one hand, the levels of identified pesticide residues and, on the other hand, those of researched TMEs (lead, cadmium, mercury and arsenic) in the waters of ponds used for fish farming in Zépréguhé, a locality located 9 km from the town of Daloa in the centre-west of Côte d’Ivoire. The dosage of the samples carried out by means of a gas chromatograph coupled to a mass spectrometer (GC/MS) made it possible to detect nine (9) pesticide molecules, including eight (8) organochlorines and a single molecule from the pyrethroid family, obtained from the detection limit of 0.006 μg/L and the quantification limit of 0.018 μg/L. The maximum average concentration was obtained with α-endosulfan for a content reaching 0.8038 μg/L and well above the maximum admissible concentration of 0.1 μg/L. The TMEs were quantified using an atomic absorption spectrophotometer (AAS). Arsenic is the most abundant metal with an average concentration of 9.497 μg/L. With the exception of lead, these measured levels are above the acceptable limit values for freshwater. This study showed that human activities such as the use of fertilisers and plant protection products in plantations, sand extraction and road traffic have a negative impact on the quality of the water in ponds used for fish breeding.

Central Hoggar groundwaters and the role of shear zones: 87Sr/86Sr, δ18O, δ2H and 14C isotopes, geochemistry and water-rock interactions

In an environment of volcanic and plutonic rocks such as the Central Hoggar, the knowledge of groundwater flows and their residence time is of prime importance. This is especially the case in the arid zone of Central Sahara where the main town of southernmost Algeria, Tamanrasset, with its rapidly growing population (>200,000 inhabitants extreme South of Algeria), put an important pressure on the local aquifers. Central Hoggar belongs to the LATEA metacraton, which is a Precambrian basement largely fractured and invaded by Cenozoic mostly basaltic volcanic rocks. In addition to superficial alluvial reservoirs, these two contrasted lithologies and large and deep faults determine the geometry of the aquifers and the nature and composition of water. We show here that distinct aquifers exist along faults oriented from NW-SE to NE-SW with no lateral communications. Some waters are in equilibrium with the Cenozoic volcanic system and others with the Precambrian basement although the latter bear often a Cenozoic volcanic signature attributed to volcanic coating along faults at depth. Alluvial, volcanic and Precambrian aquifers display contrasted measured pCO2 and specific conductivity (SC) values, stable (δ18O, δ2H), 87Sr/86Sr, 3H, δ13C and 14C isotopes. A major role is given to the Pan-African Adriane shear zone (ASZ), running just east of Tamanrasset, along which waters with high residence time (0.2<A14C < 45 pMC) are aligned in a 160–180 km long and 15 km wide corridor, including a natural soda spring (Tabahort). The latter have contrasted geochemical and isotopic signatures with respect to the other groundwaters originated from local evaporated precipitations. 87Sr/86Sr ratios vary from 0.70409 in volcanic aquifers to 0.72281 in Precambrian aquifers while C isotopes exhibit value from 0 to 117% pMC for 14C activity and δ13Cvalue from −12.5 to −2.12‰ vs VPDB. Trace elements are lower than the Maximum Admissible Concentration (MAC) except in the ASZ where Rb, Cs and U are found in higher concentrations elsewhere in Hoggar. This study enhances the peculiar status of the Central Hoggar groundwater aligned along the ASZ, close to the Tamanrasset City.

Heavy Metal Assessment in Taps Drinking Water of Ramadi City Using Water Quality Indices, Anbar Province, Iraq

This study goals to assess the concentrations of specified Heavy Metals (HMs) and quality of taps drinking water of Ramadi city, western Iraq. Heavy Metal Pollution Indices like heavy metal pollution index (HMPI ), heavy metal evaluation index (HMEI) and contamination degree (CD) were applied to assess the supplied water. The average concentrations of Lead (Pb), Nickel (Ni), Chromium (Cr), Arsenic (As) and Cadmium (Cd) in most stations exceed the maximum admissible concentration, while Iron (Fe) in most of stations was within the maximum admissible concentration according to local and global guidelines. (HMPI ) values of most stations were exceed the maximum critical value of 100. (HMEI) values of most stations were exceed the value of 10 recommended for drinking water. (CD) values of most stations were exceed the value of 1 recommended for drinking water. The pollution origins were assessed using principal component analysis (PCA) and clustering analysis (CA). The results indicate that contamination comes from anthropogenic causes being the most common and lithogenic sources being the least common. The present concentration of (HMs) in taps water is causing health and environmental problems, water with high (HMs) concentrations would need to be treated before being supplied to consumers.