A systematic review of heavy metals contamination in cosmetics

Background: Globally, the consumption and use of cosmetics have increased exponentially. The presence of hazardous metals raises worries about their potential long-term impacts on human health. Objective: This review's primary goal is to shed light on the presence and ranges of heavy metal concentrations in diverse cosmetic samples as well as the instrumental techniques used by various authors to analyse the hazardous metals in the articles under evaluation. Methodology: This analysis concentrated on 16 publications that measured the levels of heavy metals like lead, cadmium, iron, nickel, chromium, and mercury in various cosmetic samples that were published between the years 2012 and 2020. Results: The study's findings support the existence of these metals as pollutants or components in cosmetics, both of which pose substantial health hazards. The regulations and acceptable limits vary across different countries, which is a significant challenge for the cosmetic industry. Conclusion: Therefore, there is a pressing need to standardise the acceptable limits of these toxic metals in cosmetics. Instrumental techniques such as AAS, GFAAS, ICP-OES/ICP-AES, and ICP-MS were employed by Researchers to analyse the toxic metals in cosmetics.

Human health risk assessment of potentially toxic elements in soil and air particulate matter of automobile hub environments in Kumasi, Ghana

Rapid urbanization and uncontrolled industrial activities in developing countries have raised concerns about potentially toxic metal contamination of the environment. This study assessed the levels of potentially toxic elements in soil and airborne particulate matter in the Suame and Asafo areas in the Kumasi metropolis, characterized by a high concentration of auto mechanic workshops and residential settlements. X-ray fluorescence analysis and inductively coupled plasma-mass spectrometry were used to determine the metal concentrations in the samples. The results showed high concentrations of potentially toxic elements in the soil and air samples, indicating contamination from automotive activities. Metals such as Co, Ni, Pb, and Zn were found to be present at concentrations (13.42-6101.58 mg/kg and 14.15-11.74 mg/kg for Suame and Asafo respectively) that pose potential health risks to exposed populations. Mathematical models such as pollution indices were used to assess the extent of contamination and determine the potential sources of the metals - the automotive repairs. The findings highlight the urgent need for environmental management and remediation strategies to mitigate the health risks of exposure to potentially toxic elements in the Kumasi metropolis automotive hub.

Human exposure to mercury in the atmosphere and soils in Konongo: an age-old mining centre in the Ashanti Region of Ghana

The dramatic upsurge of artisanal and small-scale gold mining (ASGM) activities in Ghana has resulted in environmental degradation, water pollution and human exposure to mercury-the main hazardous element used in gold extraction. This study evaluated the degree of human exposure to mercury based on the concentrations found in the air and soil samples taken at a resolution of 1 km² across Konongo, a historic mining town in Ghana's Ashanti Region. The highest atmospheric mercury concentration was 193 ng/m³, which is much higher than the levels the European Union and Japan allowed, which are 10 ng/m³ and 40 ng/m³, respectively. The concentration in the soil was 3.6 mg Hg/kg, which is around ten times higher than the background concentration in nature. Additionally, the soil concentrations were higher above the worrisome levels of soil contamination in agricultural land (4 mg/kg) and industrial areas (16 mg/kg), respectively. Soils are extremely contaminated with mercury at sites artisanal mining activities take place. The concentrations of mercury in the air and soils were significantly higher (p < 0.5) at locations of prominent mining activities compared to areas not close to mining sites. The inhabitants of the Konongo community are therefore exposed to mercury, most likely emitted from artisanal mining activities. A non-carcinogenic risk is posed to the people by inhaling mercury vapour through the air and vapourisation from the soil. Children are exposed to a higher risk than adults as they receive higher daily doses of mercury than adults.

Characterization of inhalation exposure to gaseous elemental mercury during artisanal gold mining and e-waste recycling through combined stationary and personal passive sampling

While occupational inhalation exposure to gaseous elemental mercury (GEM) has decreased in many workplaces as mercury is being removed from most products and processes, it continues to be a concern for those engaged in artisanal and small-scale gold mining or in recycling mercury-containing products. Recently, stationary and personal passive air samplers based on activated carbon sorbents and radial diffusive barriers have been shown to be suitable for measuring GEM concentrations across the range relevant for chronic health effects. Here, we used a combination of stationary and personal passive samplers to characterize the inhalation exposure to GEM of individuals living and working in two Ghanaian gold mining communities and working at a Norwegian e-waste recycling facility. Exposure concentrations ranging from <7 ng m^-3 to >500 μg m^-3 were observed, with the higher end of the range occurring in one gold mining community. Large differences in the GEM exposure averaged over the length of a workday between individuals can be rationalized by their activity and proximity to mercury sources. In each of the three settings, the measured exposure of the highest exposed individuals exceeded the highest concentration recorded with a stationary sampler, presumably because those individuals were engaged in an activity that generated or involved GEM vapors. High day-to-day variability in exposure for those who participated on more than one day, suggests the need for sampling over multiple days for reliable exposure characterization. Overall, a combination of personal and stationary passive sampling is a cost-effective approach that cannot only provide information on exposure levels relative to regulatory thresholds, but also can identify emission hotspots and therefore guide mitigation measures.

Contamination, exposure and risk assessment of mercury in the soils of an artisanal gold mining community in Ghana

Mercury pollution has pervaded many artisanal gold mining communities in the world, especially in developing countries. This study aimed to evaluate the potential risk of mercury pollution in soils in Gbani, an artisanal gold mining community in Ghana. Two hundred and thirty-seven soil samples were collected from within 0-10 cm depth, from active mining sites near residences, two transects in the community, waste soil from mining processing and the surroundings of the community. The measured mean mercury soil concentrations were 71 mg Hg/kg in active mining sites, and more moderate (2.7 mg Hg/kg) along transects through the community. Enrichment Factors classified the soils of the study area as being moderately to extremely severely contaminated with mercury. The spatial distribution shows the contamination of mercury is highest at residential facilities and decreases through the community to the outskirts covered by vegetation. Hazard quotients for non-cancer effects identified air-borne exposure pathways for humans to pose the largest risk, including the inhalation of vapour. The average hazard indices recorded were 0.5 (child) and 0.1 (adult) at the grid, 2 (child) and 0.3 (adult) at the transects, 1.6 (child) and 0.2 (adult) for waste soil and 76 (child) and 10.9 (adult) at the mining sites. The inhabitants of Gbani community are therefore at risk of non-cancer effects of mercury as the hazard quotients and hazard index were above one.

Human health risk assessment of exposure to indoor mercury vapour in a Ghanaian artisanal small-scale gold mining community

People living or working in and around artisanal small-scale gold mining communities can be exposed to mercury vapour, which may negatively affect their health. In this study, the human exposure to air borne mercury in an artisanal mining community in the Upper East region of Ghana was investigated using Lumex RA 915 M mercury analyser, an active sampler. The concentration of mercury in air was measured inside and outside households and was related to human health risk standards. For each household, one measurement was taken from outside and three from inside at different positions. About 91% of the households where amalgam burning was reported had concentrations higher than the USEPA reference dose of 300 ng m^-3 whereas 64% of the households where amalgam burning was not reported exceeded the reference dose above. The maximal (upper) instrumental limit (50,000 ng m^-3) was passed for the highest concentrations, so, the upper 97.5% concentration was estimated, using censored statistics, to exceed 800,000 ng m^-3 for the fireplaces. This exceeds any reported indoor household air concentration of Hg, identified by the literature review in this paper. Estimated hazard quotients were found to range from <1 to 108 within the households that are reported not to burn amalgam. In the households where amalgam burning reportedly takes place, the hazard quotient had a range of 0.01-160. Mercury concentrations measured in households with reported amalgam burning are approximately ten times higher than those households with no reported burning of amalgam. The censored data predicted hazard quotients up to 966. The results indicate that both miners and non-miners of the community are at risk of adverse health effects resulting from inhalation of mercury vapour.

Human Health Risk and Bioaccessibility of Toxic Metals in Topsoils from Gbani Mining Community in Ghana

BACKGROUND

Anthropogenic activities such as artisanal mining pose a major environmental health concern due to the potential for discharge of toxic metals into the environment.

OBJECTIVES

To determine the distribution and pollution patterns of arsenic (As), iron (Fe), nickel (Ni), cobalt (Co), chromium (Cr), manganese (Mn), copper (Cu) and zinc (Zn) in the topsoil of a mining community in Ghana, along with potential human health risks and in vitro bioaccessibility.

METHODS

Concentrations of metals were determined using X-ray fluorescence techniques and validated using inductively coupled plasma-mass spectrometry.

RESULTS

Concentrations of the metals in topsoil were in the order of magnitude of Cu (31.38 mg/kg) < Ni (45.39 mg/kg) < As (59.66 mg/kg) < Cr (92.87 mg/kg) < Zn (106.98 mg/kg) < Mn (1195.49 mg/kg) < Fe (30061.02 mg/kg). Geo-statistical and multivariate analyses based on hazard indices including contamination, ecological risks, geo-accumulation, and pollution load suggest that the topsoils are contaminated in the study area. The potential ecological risk index (PERI) showed high ecological risk effects (PERI=269.09), whereas the hazard index (1×10-7) and carcinogenic risk index (1×10-5) indicated low human health risks. Elevated levels of As, Cr, Ni, and Zn were found to emanate from anthropogenic origins, whereas Fe, Mn, and Cu levels were attributed mainly to geological and atmospheric depositions. Physicochemical parameters (pH, electrical conductivity and total organic carbon) showed weak positive correlations to the metal concentrations. Elemental bioaccessibility was variable, decreasing in the order of Mn (35± 2.9%) > Cu (29± 2.6%) > Ni (22± 1.3%) > As (9± 0.5%) > Cr (4± 0.6%) > Fe (2± 0.4%).

CONCLUSIONS

Incorporation of in-vitro bioaccessibility into the risk characterization models resulted in a hazard index of less than 1, implying low human health risks. However, due to accumulation effects of the metals, regular monitoring is required.

COMPETING INTERESTS

The authors declare no competing financial interests.

Distribution of natural and artificial radioactivity in soils, water and tuber crops

Activity concentrations of radionuclides in water, soil and tuber crops of a major food-producing area in Ghana were investigated. The average gross alpha and beta activities were 0.021 and 0.094 Bq/L, respectively, and are below the guidelines for drinking water and therefore not expected to pose any significant health risk. The average annual effective dose due to ingestion of radionuclide in water ranged from 20.08 to 53.45 μSv/year. The average activity concentration of (238)U, (232)Th, (40)K and (137)Cs in the soil from different farmlands in the study area was 23.19, 31.10, 143.78 and 2.88 Bq/kg, respectively, which is lower than world averages. The determined absorbed dose rate for the farmlands ranged from 23.63 to 50.51 nGy/year, which is within worldwide range of 18 to 93 nGy/year. The activity concentration of (238)U, (232)Th, (40)K and (137)Cs in cassava ranges from 0.38 to 6.73, 1.82 to 10.32, 17.65 to 41.01 and 0.38 to 1.02 Bq/kg, respectively. Additionally, the activity concentration of (238)U, (232)Th, (40)K and (137)Cs in yam also ranges from 0.47 to 4.89, 0.93 to 5.03, 14.19 to 35.07 and 0.34 to 0.89 Bq/kg, respectively. The average concentration ratio for (238)U, (232)Th and (40)K in yam was 0.12, 0.11 and 0.17, respectively, and in cassava was 0.11, 0.12 and 0.2, respectively. None of the radioactivity is expected to cause significant health problems to human beings.