21 research outputs found
Lead and Cadmium Levels in Residential Soils of Lagos and Ibadan, Nigeria
No full textBackground. Lead and cadmium are components of paints sold in Nigeria. These heavy metals are associated with adverse neurological, cardiovascular and other human health effects.
Objectives. This study assesses the levels of lead and cadmium in topsoil of residential areas in Lagos and Ibadan potentially resulting from painting of buildings.
Methods. Samples were pre-treated prior to metal determination using atomic absorption spectrophotometry. Metal speciation was determined using modified Tessier sequential extraction. Soil characteristics were determined by standard methods. Soil contamination was assessed using contamination factor, geo-accumulation and pollution load indices. The United States Environmental Protection Agency integrated exposure uptake biokinetic (IEUBK) model was used to estimate and predict children's blood lead levels (BLL).
Results. Lead and cadmium concentrations in residential areas in Lagos and Ibadan ranged from 1.56–419 mg/kg and not detected–2.8 mg/kg, respectively. Metal contamination factor and pollution load index were highest at the Lagos low income settlement. Results of IEUBK modelling showed that the Lagos low income settlement had the highest probability density for children between 1–7 years of age with an estimated BLL of >10 μg/dL. This population made up less than 0.01% of those within this age range.
Conclusions. Lead and cadmium concentrations in soil around the residential buildings were higher than those in the control sample. Contamination factor and pollution load index showed significant contamination in average and low income settlements. These results suggested that there was accumulation of the metals in the soil, which can persist in the environment. This may pose serious health risks, especially to vulnerable groups such as children.
Competing Interests. The authors declare no competing financial interests
Lead and Cadmium Levels in Residential Soils of Lagos and Ibadan, Nigeria
No full textBackground. Lead and cadmium are components of paints sold in Nigeria. These heavy metals are associated with adverse neurological, cardiovascular and other human health effects.
Objectives. This study assesses the levels of lead and cadmium in topsoil of residential areas in Lagos and Ibadan potentially resulting from painting of buildings.
Methods. Samples were pre-treated prior to metal determination using atomic absorption spectrophotometry. Metal speciation was determined using modified Tessier sequential extraction. Soil characteristics were determined by standard methods. Soil contamination was assessed using contamination factor, geo-accumulation and pollution load indices. The United States Environmental Protection Agency integrated exposure uptake biokinetic (IEUBK) model was used to estimate and predict children's blood lead levels (BLL).
Results. Lead and cadmium concentrations in residential areas in Lagos and Ibadan ranged from 1.56–419 mg/kg and not detected–2.8 mg/kg, respectively. Metal contamination factor and pollution load index were highest at the Lagos low income settlement. Results of IEUBK modelling showed that the Lagos low income settlement had the highest probability density for children between 1–7 years of age with an estimated BLL of >10 μg/dL. This population made up less than 0.01% of those within this age range.
Conclusions. Lead and cadmium concentrations in soil around the residential buildings were higher than those in the control sample. Contamination factor and pollution load index showed significant contamination in average and low income settlements. These results suggested that there was accumulation of the metals in the soil, which can persist in the environment. This may pose serious health risks, especially to vulnerable groups such as children.
Competing Interests. The authors declare no competing financial interests.</jats:p
Trace Metals Charaterisation of Soils in the Vicinity of a Major Active Dumpsite in Lagos: An Integrative Multivariate Indices Approach
No full textHeavy metal content of selected personal care products (PCPs) available in Ibadan, Nigeria and their toxic effects
No full textAbstractThere is a growing concern on heavy metals in consumer products due to their potential human health risks and environmental effects. In this study, the levels of zinc, cadmium, lead and nickel were assessed in 3 different classes of personal care products commonly used in Ibadan, Nigeria. Samples were analysed for heavy metals using Atomic Absorption Spectrophotometer (AAS) after acid digestion. Estimated daily intake (EDI) of the metals and Health Risk Index (HRI) were calculated to assess the human health risks associated with the use of these PCPs. The concentrations (mg/kg) of zinc ranged from 3.75 to 19.3, 1.88 to 112,000 and 19.8 to 217 respectively in creams, powders and eyeliners. Cadmium ranged from ND—0.50, ND—36.3 and ND—0.50mg/kg while lead ranged from ND—6.25, ND—468 and 3.73–27.5mg/kg and nickel ranged from ND—6.25, 0.13–107 and 2.75–22.7mg/kg respectively. There were high concentrations of Cd, Pb and Ni in some of the samples when compared with the available permissible limits in cosmetics (Cd: 0.3ppm, Pb: 10ppm and Ni: 0.6ppm while there is no permissible limit for Zn in cosmetics currently available). Prolonged use of PCPs may pose human health and environmental risks due to toxic metal loading through dermal contact and accumulation over a period of time. Hence, the need for necessary government agencies to regulate and enforce toxic metals in consumer products including cosmetics produced and imported into Nigeria to safeguard public health and the environment, which is the final sink
Treatment response and remission in a double-blind, randomized, head-to-head study of lisdexamfetamine dimesylate and atomoxetine in children and adolescents with attention-deficit hyperactivity disorder
No full textA secondary objective of this head-to-head study of lisdexamfetamine dimesylate (LDX) and atomoxetine (ATX) was to assess treatment response rates in children and adolescents with attention-deficit hyperactivity disorder (ADHD) and an inadequate response to methylphenidate (MPH). The primary efficacy and safety outcomes of the study, SPD489-317 (ClinicalTrials.gov NCT01106430), have been published previously
Oxygenated Volatile Organic Compounds (Anti-freezing Agents) in Decorative Water-based Paints Marketed in Nigeria
No full textBackground. Consumer products such as paints are a potentially significant source of volatile organic compounds (VOCs) and oxygenated VOCs. Paints for construction and household use have been rapidly changing from oil-based to water-based paints and are one of the commonly identified sources of oxygenated VOCs in indoor environments.
Objectives. Four different anti-freezing agents were identified and analyzed in 174 waterbased paint samples, purchased from popular paint markets in two metropolitan cities in Nigeria, Lagos and Ibadan.
Methods. Paint samples were solvent extracted using acetonitrile and milli-Q water. Antifreezing agents in the extracts were identified and quantified using gas chromatography (GC)-mass spectrometry and a GC-flame ionization detector, respectively.
Discussion. Four different anti-freezing agents were identified in the samples, ethylene glycol, diethylene glycol, triethylene glycol and propylene glycol. Their levels ranged from 1,000-1,980 ppm, diethylene glycol; 1,000–3,900 ppm, triethylene glycol; 1,090–2,510 ppm, propylene glycol and 1,350–2,710 ppm, ethylene glycol. Levels of anti-freezing agents in all of the paint samples were above the permissible limits of the European Union for VOCs in paints of 500 ppm. Results of multivariate statistical analyses clearly showed that triethylene glycol was the most commonly used anti-freezing agent in paints despite its numerous harmful health effects.
Conclusions. We concluded that water-based paints marketed in Nigeria contain high concentrations of anti-freezing agents, which have harmful environmental and human health effects, especially to sensitive individuals such as children.
Competing Interests. The authors declare no competing financial interests.</jats:p
Vulnerability assessment of groundwater pollution in the vicinity of an active dumpsite (Olusosun), Lagos, Nigeria
No full textThe deleterious impacts of dumpsite activities and the associated risk on both the
environment and human is consequential, hence this study assessed
groundwater vulnerability to pollution from dumpsite using a modified DRASTIC
model. Six hydrogeological factors: D- Depth to water, R- Net Recharge, AAquifer
media, L- Distance of well to dumpsite, T- Topography, and C- Clay
content were used in the modification (DRALTC) based on peculiarity of the
study area. Cluster analysis of groundwater data and Water Quality Index (WQI)
were also evaluated. The groundwater vulnerability index was characterized by
two zones; forty five percent (45%) moderate and fifty five percent (55%) high
zones. The dendogram showed three clusters of chemical dissimilarities. The
WQI showed values between 61.8 and 205, indicating good, poor and very poor
class of water. The analysis of the groundwater samples showed nitrate
concentration ranging from 7.60 to 35.6 mg/L and from 8.56 to 32.4 mg/L in dry
and rainy seasons, respectively. The DRALTC model was validated using nitrate
concentration. Though, there appeared relative groundwater protection from
contamination, there is still need for measures to mitigate further contamination
and associated risk in the moderate vulnerability zones. DRALTC model is proved
a good tool in groundwater management
Oxygenated Volatile Organic Compounds (Anti-freezing Agents) in Decorative Water-based Paints Marketed in Nigeria
No full textBackground. Consumer products such as paints are a potentially significant source of volatile organic compounds (VOCs) and oxygenated VOCs. Paints for construction and household use have been rapidly changing from oil-based to water-based paints and are one of the commonly identified sources of oxygenated VOCs in indoor environments.
Objectives. Four different anti-freezing agents were identified and analyzed in 174 waterbased paint samples, purchased from popular paint markets in two metropolitan cities in Nigeria, Lagos and Ibadan.
Methods. Paint samples were solvent extracted using acetonitrile and milli-Q water. Antifreezing agents in the extracts were identified and quantified using gas chromatography (GC)-mass spectrometry and a GC-flame ionization detector, respectively.
Discussion. Four different anti-freezing agents were identified in the samples, ethylene glycol, diethylene glycol, triethylene glycol and propylene glycol. Their levels ranged from 1,000-1,980 ppm, diethylene glycol; 1,000–3,900 ppm, triethylene glycol; 1,090–2,510 ppm, propylene glycol and 1,350–2,710 ppm, ethylene glycol. Levels of anti-freezing agents in all of the paint samples were above the permissible limits of the European Union for VOCs in paints of 500 ppm. Results of multivariate statistical analyses clearly showed that triethylene glycol was the most commonly used anti-freezing agent in paints despite its numerous harmful health effects.
Conclusions. We concluded that water-based paints marketed in Nigeria contain high concentrations of anti-freezing agents, which have harmful environmental and human health effects, especially to sensitive individuals such as children.
Competing Interests. The authors declare no competing financial interests
Integration of Health Systems and Priority Health, Nutrition, and Population Interventions : A Framework for Analysis and Policy Choices
No full textA longstanding debate on health system
organization relates to the benefits of integrating programs
that emphasize specific interventions into mainstream health
systems to increase access and improve health outcomes. This
debate has long been characterized by polarization of views
and ideologies, with protagonists for and against
integration arguing relative merits of each approach.
Recently, the debate has been rekindled due to substantial
rises in externally funded programs for priority health,
nutrition, and population (HNP) interventions and an
increase in international efforts aimed at health system
strengthening. In this paper the author present a conceptual
framework and an analytical approach to define and assess
the nature and extent of integration in relation to critical
health system functions. The framework can also be used to
systematically compare and contrast programs in different
settings to generate meaningful evidence to inform policy.
In this framework, the author defines integration as the
extent, pattern, and rate of adoption and eventual
assimilation of priority health interventions into each of
the critical functions of a health system, which include,
inter alia: (i) governance, (ii) financing, (iii) planning,
(iv) service delivery, (v) monitoring and evaluation, and
(vi) demand generation. The framework and the analytical
approach are intended for evaluative and formative studies
of policies, systems, and programs
Pollution vulnerability and health risk assessment of groundwater around an engineering landfill in Lagos, Nigeria
No full textSolid wastes disposal, through the use of non-sanitary landfill facility has tremendous health impacts on man and environment, yet without regard to environmental consequences, the use of controlled dumpsite is at best a common practice in underdeveloped countries. The paucity of data on modelling of potential vulnerability of neighboring aquifer to the pollution from Soluos dumpsite (a non-engineering landfill) necessitate the study of the use of a model DRALTC (modified DRASTIC) on the estimation of vulnerability of groundwater to dumpsite pollution and associated health risks. Six hydrogeological factors: Depth to water, net recharge, aquifer media, distance of wells to dumpsite, topography, and clay content, were involved in the modification of the model (DRALTC) which helps in characterizing the hydrogeological setting of the study area and estimation aquifer vulnerability. Sodium adsorption ratio (SAR) and permeability index (PI) were used to analyse the data generated in this study. The health risk indices (HRI) were also estimated for trace metals in the groundwater samples. The pollution vulnerability ranged between (161 and 175) moderate and high groundwater pollution potential. SAR results observed in this study reveal 25% excellent, 20 % good, 10% doubtful and 45% unsuitable. The order HRI observed was Cd > Zn > Cu > Ni > Pb for adult, while Cd > Cu > Ni > Zn >Pb trend was found for children, though the HRI value for all the metals investigated were within the safe limit (HRI < 1.0) suggesting no health risk
