Analytical determinations in soils, Standardization of methods. II. Potasium, Calcium and magnesium

After our first paper about the determination of pH. organic matter and nitrogen appeared few years agc, our Group has followed working on the standardization of methods to be applied to the analytical determinations of soils. This second paper deals with the determination of extractable potassium, calcium and magnesiumPeer reviewe

Chromosomal bands affected by acute oil exposure and DNA repair errors

Background: In a previous study, we showed that individuals who had participated in oil clean-up tasks after the wreckage of the Prestige presented an increase of structural chromosomal alterations two years after the acute exposure had occurred. Other studies have also reported the presence of DNA damage during acute oil exposure, but little is known about the long term persistence of chromosomal alterations, which can be considered as a marker of cancer risk. Objectives: We analyzed whether the breakpoints involved in chromosomal damage can help to assess the risk of cancer as well as to investigate their possible association with DNA repair efficiency. Methods: Cytogenetic analyses were carried out on the same individuals of our previous study and DNA repair errors were assessed in cultures with aphidicolin. Results: Three chromosomal bands, 2q21, 3q27 and 5q31, were most affected by acute oil exposure. The dysfunction in DNA repair mechanisms, expressed as chromosomal damage, was significantly higher in exposed-oil participants than in those not exposed (p= 0.016). Conclusion: The present study shows that breaks in 2q21, 3q27 and 5q31 chromosomal bands, which are commonly involved in hematological cancer, could be considered useful genotoxic oil biomarkers. Moreover, breakages in these bands could induce chromosomal instability, which can explain the increased risk of cancer (leukemia and lymphomas) reported in chronically benzene-exposed individuals. In addition, it has been determined that the individuals who participated in clean-up of the oil spill presented an alteration of their DNA repair mechanisms two years after exposure.For this study was provided by grants from the Health Institute Carlos III FEDER/ERDF (PI03/1685), Sociedad Española de Neumología y Cirugía Torácica (SEPAR), Comissionat per a Universitats i Recerca from Generalitat de Catalunya (SGR09-1107), Centro de Investigación en Red de Enfermedades Respiratorias and Universidad Autónoma de Barcelona (PS-456-01/08)

A review of the available phosphorus extraction methods in soils (1957-1980)

Trabajos recapitulativos.- Grupo de trabajo de normalización de métodos analíticosA compilation of the most important methods is presented. This paper is divided into four parts: I) Brief description of new methods or modifications of the previous ones; 2) paper where a comparison of methods have been made; 3) particular application of the Bray-Kurtz method. and 4) particular application of the Olsen method.Peer reviewe

Health effects of non-occupational exposure to oil extraction.

Oil extraction may cause extensive environmental impact that can affect health of populations living in surrounding areas. Large populations are potentially exposed to oil extraction related contamination through residence in areas where oil extraction is conducted, especially in low and middle income countries (LMICs). Health effects among people residentially exposed to upstream oil industry contaminants have been poorly studied. Health effects of exposure to oil related contamination have been mainly studied among cleanup workers after oil spills from tankers or offshore platforms.In this paper we aim to identify the type and extension of residential exposures related to oil extraction activities and to comment on the few health studies available. We estimated that 638 million persons in LMICs inhabit rural areas close to conventional oil reservoirs. It is relevant to specifically study people residentially exposed to upstream oil industry for the following reasons: First, persons are exposed during long periods of time to oil related contamination. Second, routes of exposure differ between workers and people living close to oil fields, who can be exposed by ingestion of contaminated waters/foods and by dermal contact with contaminated water and/or land during daily activities (e.g. bathing, agricultural activities, etc.). Third, individuals potentially more susceptible to the effect of oil related contamination and not normally occupationally exposed, such as infants, children, pregnant women, elderly or people with previous health conditions, are also exposed.There are few papers studying the potential health effects of residential exposure to oil related contamination, and most of them share important limitations. There is a need for more research through the conduct of methodologically robust studies in exposed populations worldwide. Despite the difficulties in the conduct of studies in remote areas, novel approaches, such as measurement of individual exposure using biomarkers of exposure and effect, should be used. These studies should be promoted to understand the health risks associated to residential exposure to oil related contamination, support effective control policies to avoid such contamination and to sustain public health recommendations and policies to avoid exposure in already contaminated areas.C.O.G holds a Sara Borrell postdoctoral fellowship awarded from the Carlos III National Institute of Health (CD13/00072). M.O.M. benefited from the financial support of the ‘Conflict and Cooperation over Natural Resources in Developing Countries’ program of The Netherlands Organisation for Scientific Research (NWO) - www.iss.nl/nebe- and the ‘International Initiative for Impact Evaluation’ (3ie)