Chemical, biological, and ecotoxicological assessment of pesticides and persistent organic pollutants in the Bahlui River, Romania

Background, aim, and scope  

Current knowledge on environmental impacts of industrial activities in Romania, particularly persistent organic pollutants (POPs), indicates that environmental standards of the European Union are not systematically met. In our study area, additional sources of POPs are agriculture and domestic wastes. Very scarce information is available upon environmental contaminations and effects. In the present study, we investigated the chemical pollution and their eventual impact on the ecosystem by measuring POPs and by using biological indicators of pollution.     

Evaluation of the aggressive potential of marine chloride and sulfate salts on mortars applied as renders in the Metropolitan Region of Salvador--Bahia, Brazil

In recent years, growing interest has focused on determining the performance of materials and evaluating the service life of structures exposed to various environmental forces. In this context, the determination of the aggressive potential of marine salts on mortars used as external renders is critical. The present study aimed to evaluate the spatial distribution of marine salts relative to distance from the sea. This was done by monitoring the deposition rate of chlorides and sulfates in wet candle sensors, located at nine stations scattered around the Metropolitan Region of Salvador, state of Bahia, Brazil. The study also determined the effectiveness of water-soluble salts at penetrating three different types of mortars of varying cement content via deposition and diffusion. The methodology employed enabled an evaluation of the efficiency of the monitoring sensors' measurement of the aggressiveness potential of local marine aerosol, and determination of the comparative performance of the three mortars tested, from the standpoint of resistance to salt penetration. The type and amount of salts captured both in solution and in powder samples extracted from the mortars were determined by ion chromatography. The analysis of the various types of mortars tested indicated which types are more resistant to the aggressive potential of the region's marine aerosol and the distance from the shore where local buildings are liable to be most strongly affected.     

Sulfate removal from waste chemicals by precipitation

Chemical oxidation using Fenton's reagent has proven to be a viable alternative to the oxidative destruction of organic pollutants in mixed waste chemicals, but the sulfate concentration in the treated liquor was still above the acceptable limits for effluent discharge. In this paper, the feasibility of sulfate removal from complex laboratory wastewaters using barium and calcium precipitation was investigated. The process was applied to different wastewater cases (two composite samples generated in different periods) in order to study the effect of the wastewater composition on the sulfate precipitation. The experiments were performed with raw and oxidized wastewater samples, and carried out according to the following steps: (1) evaluate the pH effect upon sulfate precipitation on raw wastewaters at pH range of 2-8; (2) conduct sulfate precipitation experiments on raw and oxidized wastewaters; and (3) characterize the precipitate yielded. At a concentration of 80 g L(-1), barium precipitation achieved a sulfate removal up to 61.4% while calcium precipitation provided over 99% sulfate removal in raw and oxidized wastewaters and for both samples. Calcium precipitation was chosen to be performed after Fenton's oxidation; hence this process configuration favors the production of higher quality precipitates. The results showed that, when dried at 105 degrees C, the precipitate is composed of hemidrate and anhydrous calcium sulfate ( approximately 99.8%) and trace metals ( approximately 0.2%: Fe, Cr, Mn, Co, Ag, Mg, K, Na), what makes it suitable for reuse in innumerous processes.     

Incomes,Attitudes, and Occurrences of Invasive Species: An Application to Signal Crayfish in Sweden

This article analyzes and carries out an econometric test of the explanatory power of economic and attitude variables for occurrences of the nonnative signal crayfish in Swedish waters. Signal crayfish are a carrier of plague which threatens the native noble crayfish with extinction. Crayfish are associated with recreational and cultural traditions in Sweden, which may run against environmental preferences for preserving native species. Econometric analysis is carried out using panel data at the municipality level with economic factors and attitudes as explanatory variables, which are derived from a simple dynamic harvesting model. A log-normal model is used for the regression analysis, and the results indicate significant impacts on occurrences of waters with signal crayfish of changes in both economic and attitude variables. Variables reflecting environmental and recreational preferences have unexpected signs, where the former variable has a positive and the latter a negative impact on occurrences of waters with signal crayfish. These effects are, however, counteracted by their respective interaction effect with income.     

Organochlorine and heavy metals in newborns: Results from the Flemish Environment and Health Survey (FLEHS 2002–2006)

To collect regional information on internal levels of pollutants in humans in Flanders, 1196 mother–child pairs were systematically recruited in 2002–2003 via 25 maternities across Flanders. Cd, Pb, PCB congeners 118, 170, 138, 153 and 180, p,p′-DDE — a key metabolite of DDT- and hexachlorobenzene (HCB) were measured in cord blood or plasma. Cd was detected in 64% of the samples (geometric mean 0.21 µg/L cord blood). p,p′-DDE (110 ng/g plasma lipids) and Pb (14.7 µg/L blood), were measurable in nearly all samples. The individual PCB congeners could be detected in 40 to 81% of the newborns (138 + 153 + 180 = 64.4 ng/g plasma lipids). HCB (18.9 ng/g plasma lipids) and dioxin-like compounds measured by DR-CALUX® (23 pg CALUX-TEQ/g lipids) were above detection limit in more than 75% of the samples. Age and smoking habits of the mothers, did not influence the cord blood Pb and Cd levels. The organochlorines increased 4 to 9% per year of the mother's age (partial R² = 0.05 to 0.22). Mothers had 2.6% less PCBs in cord blood (partial R² = 0.02) for each unit increase in pre-pregnancy BMI. Season of delivery, breastfeeding previous children or consumption of local dairy products, were minor determinants. Up to 20% of the variability in organochlorine concentrations was explained by residence area. It was concluded that the place of birth in Flanders is an important determinant of the load of pollutants measured at the start of life. This underlines the validity of human biomonitoring on (relatively) small geographical scale.     

Lactational exposure to phthalates in Southern Italy

BackgroundPhthalates, reproductive toxicants in animals, are synthetic chemicals with ubiquitous human exposures because of their extensive use, with potential detrimental health effects. Infants are considered to represent a population at increased risk, as they are exposed early in life to several different sources of exposure to phthalates.Objectives and methodsLittle information exists on phthalate exposure through breast milk from different geographic areas. By means of a LC/LC–MS/MS method we tested the presence of several different phthalate metabolites in breast milk from 62 healthy mothers living in Southern Italy.ResultsThe simple monoesters mono-isobutyl phthalate (MiBP) (median 18.8 μg/l) and mono(2-ethylhexyl) phthalate (MEHP) (median 8.4 μg/l) were present in all milk samples, whereas mono-n-butyl phthalate (MnBP) (median 1.5 μg/l) and mono-benzyl phthalate (MBzP) (median < 0.3 μg/l) were found in 64.5% and 43.5% of the samples, respectively. Among the oxidative metabolites of DEHP and DiNP only mono(2-ethyl-5-carboxypentyl) phthalate (5cx-MEPP) and monoisononyl phthalate with one hydroxyl group (OH-MiNP) were detectable in one and 13 samples (21%), respectively.ConclusionsThese findings indicate that exposure to phthalates through breast milk in Southern Italian infants is comparable to that of other countries, thus confirming that human milk may represent an additional potential source of phthalate exposure in a population at increased risk. However, different milk concentrations of MiBP may suggest a different pattern of usage of di-iso-butyl phthalate in Europe, as compared to USA, whereas for the first time, we detected an oxidative DiNP metabolite, whose significance remains unclear.     

The toxicity of sulfamethazine to Daphnia magna and its additivity to other veterinary sulfonamides and trimethoprim

Sulfonamides (SAs), the oldest chemotherapeutic agents used for antimicrobial therapy, still play an important role in veterinary mass treatments. Consequently, traces of these compounds, alone or in combinations, have been repeatedly detected in the environment. Sulfamethazine (SMZ) deserves particular attention not only because it is the most used veterinary SA, but also due to its proven effects on fertility in mice and on thyroid hormone homeostasis in rats. In this study, after evaluating the acute toxicity to Daphnia magna of six veterinary SAs and trimethoprim (TMP), the additivity of SMZ to each other compound was tested using the isobologram method. Two reproduction tests on the same biological model were also performed in order to derive LOEC and NOEC of SMZ. The acute EC₅₀ was in the range 131–270 mg L⁻¹ for all the compounds tested with the exception of sulfaguanidine (EC₅₀ = 3.86 mg L⁻¹). In acute binary tests SMZ showed a complex interaction with sulfaquinoxaline (superadditivity, additivity or subadditivity) at the three different combination ratios tested, simple additivity to TMP and less than additive interaction when paired to the other SAs. LOEC and NOEC of SMZ obtained from reproduction tests were 3.125 and 1.563 mg L⁻¹, respectively. In conclusion, SMZ should not harm the crustacean population at environmentally realistic concentrations. Its toxicity is comparable to that of other systemic SAs, and their binary interactions are less than additive. The same can not be entirely said for enteric SAs, and considering that these compounds are administered at high doses and mostly excreted in unmetabolised form, further evaluation of their impact to the aquatic environment seems advisable.     

Role of Alternative Electron Acceptors (AEA) to control methane flux from waterlogged paddy fields: Case studies in the southern part of West Bengal, India

The rice fields, depleted of O₂, contain large amount of moisture and organic substrates to provide an ideal anaerobic environment for methanogenesis and are one of the principal anthropogenic sources of methane. In order to mitigate this emission Alternative Electron Acceptors (AEA) were altered in the soil. The experiments were carried out in four seasons at the site of Balarampur, near Baruipur, South 24 Parganas, West Bengal, namely September–December, 2005 (Cultivar: Sundari), February–May, 2006 (Cultivar: Sundari), September–December, 2006 and February–May, 2007 (Cultivar: Swarna-Pankaj). The seasonal average methane flux (Fe treated), for the cultivar type “Sundari” (season: September–December, 2005), is 4.41 t ha⁻¹, as compared to the value of 6.40 t ha⁻¹ for the untreated soil. Similarly for February–May, 2006, the seasonal average methane flux (Fe treated) is 5.52 t ha⁻¹, whereas the untreated flux is 5.69 t ha⁻¹. In the third and fourth seasons we had two treatments with Ammonium Thiosulphate and Ferric Hydroxide. The seasonal average methane flux (treatment: Ammonium Thiosulphate) is 4.35 t ha⁻¹ and 5.41 t ha⁻¹ respectively, whereas for the ferric hydroxide treated soil it is 4.35 t ha⁻¹ and 6.14 t ha⁻¹ respectively. The properties related to the nutrient quality of the harvested paddy seeds supplement these results.     

A survey on the public perception of CCS in France

An awareness and opinion survey on carbon capture and storage (CCS) was conducted on a representative sample of French residents aged 15 years and above. About 6% of respondents were able to provide a satisfactory definition of the technology. The key question about ‘approval of or opposition to’ the use of CCS in France was asked twice, first after presenting the technology, then after explaining its potential adverse consequences. The approval rates, which were 59% and 38%, respectively, show that there is no a priori rejection of the technology. The sample was split in two to test for a semantic effect: half of the questionnaires used “Stockage” (English: storage), the other half “Sequestration”. Manipulating the vocabulary had no statistically significant effect on approval rates. Stockage is more meaningful, but does not convey the idea of permanent monitoring.