Background. Little importance has been placed on sustainability of the Papanicolaou (Pap) stain, the gold standard for the diagnosis of cervical cancer, for global environmental health. The standard Pap stain uses environmentally toxic and carcinogenic reactants such as xylene, hydrochloric acid and ammonia solution. Objectives. To eradicate the use of environmentally toxic and carcinogenic reactants through the validation of the Ecologic Papanicolaou (Eco-Pap) test. Methods. Reagent handling strategies were divided in three phases: used Harris' progressive hematoxilin, polychromatic solution and direct mounting that were analyzed by PEED-Cytology, Staining Quality Index (ICT) and the Bethesda system 2014. Results. A total of 52,319 Pap smears stained with Eco-Pap were admitted (ICT=0.91). Validation of the Eco-Pap versus conventional staining was optimal (Kappa =0.89) and the sensitivity and specificity of the method were 57% and 98%, respectively. Eco-Pap reduced the environmental contamination produced by xylene (66 liters), hydrochloric acid and ammonia (5.5 liters each) over nine months, and all diagnoses coincided with the cytological details. Conclusions. The Eco-Pap is an innovative method that transforms Pap testing into a sustainable and supportable technology.

Agricultural practices are usually supported by several chemical substances, such as herbicides. Linuron and chlorbromuron are phenylurea herbicides largely used to protect crops from weeds, blocking photosynthesis by inhibition of the photosystem II complex. The former, also commercially known as lorox or afalon, is selectively used to protect bean and French bean plants, fennels, and celeriacs; the second, commercially known as maloran, is selectively used for carrots, peas, potatoes, soy sprouts, and sunflowers. Considering the widespread use of herbicides and, more generally, pesticides, it is important to clarify their involvement on human health, one of them concerning the possible direct or indirect effect on the genome of exposed populations. Here, we show that these herbicides are endowed by mutagenic properties, as demonstrated by an increased number of chromosomal aberrations (CAs) in two exposed Chinese hamster cell lines derived from ovary and epithelial liver, respectively. This was also confirmed by sister chromatid exchange (SCE) and micronucleus (MN) assays. Our present and previously obtained data clearly indicate that phenylurea herbicides must be used with great caution, especially for agricultural workers who use large amounts of herbicides during their work, and particular attention should be given to residues of these herbicides and their involvement in environmental pollution.

The National Environment Council (CONAMA Resolution 375/06) defined to achieve sanitation quality parameters, for the use of sewage sludge in agriculture, the adoption of additional pathogen reduction processes is necessary. Sludge that is stored for longer periods generally shows higher levels of sanitation, particularly on the helminth egg inactivations which are among the most resistant pathogens. The objective of this study was to monitor the Ascaris egg removal and inactivation efficiency of long-term storage of sludge from septic tanks and up-flow anaerobic sludge blanket (UASB) reactors, besides evaluating the influence of covering and manually revolving or stirring the sludge over a 2-year period. The study was undertaken in the cities of Fazenda Rio Grande and Apucarana, Southern Brazil. In total, 18 experimental treatments were installed and nine samples were assessed at weeks 0, 4, 9, 13, 17, 30, 47, 61, and 104. The standard defined in the CONAMA for class A sludge (one viable egg per 4 g TS) was reached for all treatments at 9 weeks of storage. Two years of storage were necessary in order for the covered, UASB-centrifuge sludge to reach CONAMA standards. Of the six treatments using septic sludge, only one achieved the established standard. This treatment was realized in Apucarana and involved a revolving/stirring process. The period of 104 weeks of storage of the septic sludge was not sufficient to completely inactivate Ascaris eggs for the other treatments. Between study locations, Apucarana performed better than Curitiba which is likely due to greater levels of insolation and temperature.

Background. Child exposure to lead from informal used lead-acid battery (ULAB) recycling operations is a serious environmental health problem, particularly in developing countries. Objectives. We investigated child exposure to lead in the vicinities of ULAB recycling operations in the Dandora, Kariobangi and Mukuru slums in Nairobi between January and August 2015. Methods. Top soil (n = 232) and floor dust (n = 322) samples were collected from dwelling units (n = 120) and preparatory schools (n = 44) and analyzed using an inductively coupled plasma-optical emission spectrometer at the Mines and Geological Department Laboratory in the Ministry of Mining, Nairobi. From the obtained lead levels in soil and house dust, child blood lead levels were subsequently predicted using the Integrated Exposure Uptake Biokinetic Model for Lead in Children (IEUBK), Windows version. Results. Lead loadings in all the floor dust samples from the Dandora, Kariobangi and Mukuru slums exceeded the United States Environmental Protection Agency (USEPA) guidance value for lead on floors with a range of 65.2 – 58,194 μg/ft2. Control floor dust samples recorded lower lead loadings compared to the Dandora, Kariobangi and Mukuru slums. Lead concentration in 70.7% of the soil samples collected from waste dumps, industrial sites, residential areas, playgrounds and preparatory schools in Dandora, Kariobangi and Mukuru exceeded the respective USEPA guidance values for lead in soils. Lead concentration in 100% of control soil samples were below the respective USEPA limits. The IEUBK model predicted that nearly 99.9% of children ≤ 7 years old living near informal ULAB recycling operations in Dandora, Kariobangi and Mukuru were at risk of being lead poisoned, with predicted blood lead levels (BLL) above the Centers for Disease Control (CDC) reference value for blood lead. A total of 99.9% of exposed children living in the Mukuru slums are likely to have BLL above 34 μg/dL. Conclusions. There is a need for coordinated efforts to decrease lead emissions from informal battery recycling in Nairobi slums and to remediate existing soils, particularly around battery workplaces and dumpsites. The BLL of local children should be clinically tested and appropriate intervention measures taken. Competing Interests. The authors declare no competing financial interests.

Background. Unsound recycling of e-waste releases toxic metals into environmental media and has deleterious health consequences to humans as the metals transfer to humans through the food chain, direct contact and inhalation. Objectives. This study assessed soil contamination with lead (Pb), copper (Cu), chromium (Cr), nickel (Ni) and cadmium (Cd) arising from crude e-waste recycling. Methods. Forty-eight soil samples were collected from the vicinity of high-, medium- and low-activity recycling operations in Ogunpa in Ibadan, Nigeria as well as from the botanical garden of the University of Ibadan for background samples. Total extractable metals were leached with aqua regia and the leachates were analyzed using flame atomic absorption spectrometry. Speciation analysis was also conducted on soil samples that showed high concentrations of metals to determine the distributions in various phases. Results. All soil samples were determined to be sandy loam in composition with pH and organic matter ranging from 7.1–7.9 and 1.56–1.81%, respectively. Metal concentrations (mg/kg) for soils from the study area ranged as follows: Pb, 269 – 5650; Cu, 203 – 3483; Cr, 3.30 –42.4; Ni, 0.14 – 24.0; and Cd, below detection limit – 2.50. The results indicated enrichment in soil by all metals, especially Pb and Cu, which were many times higher compared with background concentrations. Additionally, average Pb and Cu concentrations were higher than regulatory limits for soil set by selected countries across the globe. Speciation studies indicated that about 65% and 88% of Pb and Cu, respectively, were liable to potential mobility with slight changes in natural conditions. Other metal concentrations, although with higher concentrations compared with background levels, were within the permissible limits in soils accepted by many countries across the globe. There were significant correlations between all metals, suggesting that they may have been released from a common source. Conclusions. Soils from the study area require urgent clean-up, especially for Pb and Cu, to safeguard human health and the environment. Competing Interests. The authors declare no competing financial interests.

Background. Polychlorinated biphenyls (PCBs) are organic compounds, known to be carcinogenic and banned by the Stockholm Convention. PCBs are hydrophobic substances able to accumulate in organic materials, including plastic pellets. Plastic resin pellets are industrial raw materials that are remolded finished products for industrial and domestic use, commonly used for packaging. Plastic resin pellets were chosen as the medium for monitoring hydrophobic contaminants because they are able to adsorb PCB contaminants. Pellets can be unintentionally washed into the ocean where hydrophobic contaminants such as PCBs are also deposited. Objectives. We aimed to identify PCB congeners and quantify PCB pollution levels in the marine environment using resin plastic pellets collected from six beaches along the Accra-Tema coastline in Ghana. Methods. Plastic resin pellets (5 g) were extracted with 200 mL of n-hexane for 16 hours by Soxhlet extraction. Concentrations of PCBs from the extracts were determined using gas chromatography with an electron capture detector. Results. The individual PCB congeners detected were PCB 28, 52, 101, 105, 138, 153, 156 and 180. PCB 28 was detected at all six beaches, with a total concentration of 43.5 ng/g pellet (mean/beach 7.25 +/− 2.47 ng/g pellet; CV = 34%), while PCB 138 was only detected on one beach (Castle Beach) at a total concentration of 0.8 ng/g pellet. The concentration of PCBs ranged from 7.4 ng/g (Sunset Beach) to 47.5 ng/g (Castle Beach) (mean 16.4±15.4 ng/g per beach; CV=94%). Discussion. PCB concentrations at Castle Beach have been studied previously, showing an increase from 39 ng/g to 47.5 ng/g, whereas levels decreased significantly from 28 ng/g to 14.2 ng/g in Sakumono Beach over the span of three years. Conclusions. The concentrations of four detected PCB congeners (28, 52, 101 and 156) were significantly higher than the World Health Organization (WHO) allowable daily intake of 6 ng/g food per day for PCBs. A more efficient industrial and domestic waste disposal system is advocated for Ghana. Competing Interests. The authors declare no competing financial interests.

Background. Heavy metals in water systems are a human health concern as they can enter the food chain. Objectives. Heavy metal and particle size determinations were used to determine the sediment quality of three fishponds in Osun State, Nigeria and their feeder streams. Methods. Sediment samples were collected in triplicates from the streams and their associated fishponds and the accumulations of nine heavy metals (lead (Pb), cobalt (Co), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), iron (Fe), manganese (Mg), zinc (Zn)) in the sediment were investigated seasonally. Particle size distribution and textural class of the samples were also determined. Results. Metal concentrations recorded in bottom sediment varied widely and exhibited fluctuations among the different ponds and streams, especially in the values of Fe, Cu, Mn, Cr, Zn and Pb. There was a significant difference (p<0.05) in the concentrations of metals across the three investigated locations. The metals in the sediments occurred in the order of Fe>Cu>Ni>Zn>Pb>Cr>Mn>Co in Ilesha, Fe>Cu>Ni>Zn>Mn>Co>Pb>Cr in Osogbo and Zn>Fe>Ni>Mn>Cu>Co>Cr>Pb in Yakoyo. A closely related order of Fe>Mn>Ni>Zn>Cr>Cu>Se>Pb>Mo>Cd was observed in River Eku. The selected streams and their associated fishponds were fairly polluted, with the Yah fishpond (Ilesha) having the highest heavy metal pollution compared to Arula fishpond (Osogbo) and Ewuru/Rara fishpond (Yakoyo). The concentrations of accumulated heavy metals depended on the textural class of the sediment. Conclusion. Pollution has reached levels hazardous to human health compared to standard limits for aquaculture development. Stream and fishpond sediments should be analyzed at regular intervals as a quality assurance process to ensure that there are no toxic substances in the ponds, leading to possible bio-accumulation and magnification. This will help guarantee the health of the aquatic ecosystem, humans and the environment. Competing Interests. The authors declare no competing financial interests.

Background. Contamination of drinking water with heavy metals poses a human health threat, particularly in low-income countries where point-of-use water purification systems are beyond the reach of a majority of households. Objectives. The study was undertaken to evaluate the efficacy of Acacia galpinii (monkey thorn tree) biomass in removing lead (Pb (ll)), cadmium (Cd (ll)), calcium (Ca (ll)), and magnesium (Mg (ll)) ions from drinking water. Methods. A. Galpinii biomass from seed and seed pods was processed by pulverizing, Soxhlet oil extraction and particle size grading. The material was analyzed by X-ray fluorescence (XRF) and Fourier transform infrared (FTIR) spectrophotometry. Influence of the physiochemical parameters (contact time, initial concentration, adsorbent dosage, pH) on the effectiveness of the biomass in removing Pb (ll), Cd (ll), Ca (ll) and Mg (ll) ions was evaluated and the best fit adsorption isotherm model (Langmuir vs. Freundlich) was also determined. Results. Particle size, dose, contact time and pH all played significant roles in the effectiveness of metal removal for both seed and seed pod biomass. At biomass particle size <90 microns, 98% removal rates of Pb (II) ions were achieved for powdered seed pods compared with 65% for powdered seeds. The same trend was observed for Cd, Ca and Mg. Contact time for effective removal of metal ions by pod powder and seed powder was 90 minutes and 120 minutes, respectively. Maximum adsorption was achieved at solution pH 6-8 for all metals. Lead adsorption followed a Langmuir isotherm model with maximum adsorption capacities of 10.8932 for pod powder and 3.4412 for seed powder. Adsorption of Ca and Mg followed a Freundlich model, with adsorption capacity of 1.1789 for Ca and 1.4521 for Mg. Conclusions. Acacia galpinii seeds and seed pods are inexpensive, readily available and may serve as a cost effective means for treatment of drinking water for domestic users in low and middle income countries. Competing Interests. The authors declare no competing financial interests.

The effect of direct current (DC) on phenol biodegradation under aerobic/anaerobic condition was investigated in this study using a bioelectrochemical reactor. It was found that phenol biodegradation was inhibited with current ranged from 10 to 40 mA. The growth of biomass was reduced to 43.2 ± 6.6 % for aerobic sludge and 38.6 ± 7.3 % for anaerobic sludge, but the loosely bound extracellular polymer substances (LB–EPS) were increased 91.2 ± 1.3 % for aerobic sludge and 62.8 ± 0.8 % for anaerobic sludge as the current increased from 10 to 40 mA. Adenosine triphosphate (ATP) content of aerobic sludge was also reduced 0.481 ± 0.04-fold and 0.512 ± 0.05-fold lower and 1.34 ± 0.13-fold higher than that of the control when the current was increased from 10 to 40 mA. The results of phosphate buffer saline adding treatment indicated that lower pH caused by a DC above 10 mA was responsible for the reduced phenol biodegradation, leading to the reduction of biomass. However, lower intensity of current (5 mA) had no significant impact on phenol degradation rate, pH, LB–EPS, ATP content, and cell growth of aerobic/anaerobic sludge. These results give us a more detailed understanding of the effects of electricity on the treatment of phenol containing wastewater.

Adsorption of arsenic (III, V) from aqueous solution onto the synthesized α-Fe₂O₃/MCM-41 nanocomposite adsorbent, as function of contact time, initial concentration of the solution, temperature, pH, and presence of other anionic species, has been investigated. Characterization of adsorbent was performed via XRD, FT-IR, TGA, TEM, and N₂ adsorption–desorption techniques. The synthesized adsorbent belonged to the group of mesoporous materials with the mean pore diameter of 2.37 nm, specific surface area of 507.5 m² g⁻¹, and total pore volume of 0.571 cm³ g⁻¹. The experimental data were analyzed by Langmuir, Freundlich, and Dubinin-Radushkevich (D–R) adsorption isotherms. Based on Langmuir isotherm, the maximum adsorption capacities at 298 K in the concentration range of 2–200 ppm were 133.3 and 102.1 mg g⁻¹ for As(ш) and As(v), respectively. The adsorption experiments at different contact times indicated that the kinetics of adsorption accurately followed the pseudo-second-order rate equation. Thermodynamics parameters were calculated, and it was found that the adsorption process was spontaneous, exothermic, and favored at lower temperatures. The capability of regeneration and reusability of adsorbent was also examined in alkaline solutions.