Prepandemic personal concentrations of per- and polyfluoroalkyl substances (PFAS) and other pollutants: Specific and combined effects on the incidence of COVID-19 disease and SARS-CoV-2 infection.

OBJECTIVE: To investigate the specific and combined effects of personal concentrations of some per- and polyfluoroalkyl substances (PFAS), other persistent organic pollutants (POPs), and chemical elements -measured in individuals' blood several years before the pandemic- on the development of SARS-CoV-2 infection and COVID-19 disease in the general population. METHODS: We conducted a prospective cohort study in 240 individuals from the general population of Barcelona. PFAS, other POPs, and chemical elements were measured in plasma, serum, and whole blood samples, respectively, collected in 2016-2017. PFAS were analyzed by liquid chromatography-triple quadrupole mass spectrometry. SARS-CoV-2 infection was detected by rRT-PCR in nasopharyngeal swabs and/or antibody serology in blood samples collected in 2020-2021. RESULTS: No individual PFAS nor their mixtures were significantly associated with SARS-CoV-2 seropositivity or COVID-19 disease. Previously identified mixtures of POPs and elements (Porta et al., 2023) remained significantly associated with seropositivity and COVID-19 when adjusted for PFAS (all OR > 4 or p < 0.05). Nine chemicals comprised mixtures associated with COVID-19: thallium, ruthenium, lead, benzo[b]fluoranthene, DDD, other DDT-related compounds, manganese, tantalum, and aluminium. And nine chemicals comprised the mixtures more consistently associated with SARS-CoV-2 seropositivity: thallium, ruthenium, lead, benzo[b]fluoranthene, DDD, gold, and (protectively) selenium, indium, and iron. CONCLUSIONS: The PFAS studied were not associated with SARS-CoV-2 seropositivity or COVID-19. The results confirm the associations between personal blood concentrations of some POPs and chemical elements and the risk of COVID-19 and SARS-CoV-2 infection in what remains the only prospective and population-based cohort study on the topic. Mixtures of POPs and chemical elements may contribute to explain the heterogeneity in the risks of SARS-CoV-2 infection and COVID-19 in the general population.

[Chemical pollution, exposome and health in the Canary Islands population: An assessment of the situation.] / Contaminación química, exposoma y salud en la población de las Islas Canarias: una revisión sistemática de los estudios realizados y análisis de la situación.

OBJECTIVE: The set of exposures to chemical substances and their role as a cause of disease gives rise to the concept of the exposome, partially made up of chemical pollutants to which an individual is exposed, which is why, unlike the genome, it is an a priori modifiable factor, its study being crucial in terms of Public Health. The population of the Canary Islands has been studied in terms of its levels of chemical contamination, with numerous biomonitoring studies, which makes it necessary to characterise its exposome and its consequences in terms of disease, in order to implement specific corrective measures to minimize the impact on its health. METHODS: A review of scientific literature (MEDLINE and Scopus) was made, according to PRISMA criteria and PICO methodology, to include studies on biomonitoring of pollutants, or evaluating the effect of pollutants on diseases prevalent in the archipelago. RESULTS: Twenty-five studies, both population-based and hospital-based, were selected. The results show that the exposome is made up of at least 110 compounds or elements, 99 of which appear to be present from the intrauterine stage. The presence of chlorinated pollutants and metals stands out, which seems to be related to the high incidence of metabolic diseases (diabetes), cardiovascular diseases (hypertension) and certain types of neoplasms (breast cancer). In short, the consequences are conditioned by the genome of the exposed population, reinforcing the enormous importance of genome-exposome interactions in the development of pathologies. CONCLUSIONS: Our results indicate that it is necessary to establish corrective measures on the sources of pollution that modify the exposome of this population.

OBJETIVO: El conjunto de exposiciones a sustancias químicas y su papel como causa de enfermedad da lugar al concepto de exposoma, conformado parcialmente por contaminantes químicos a los que un individuo se ve expuesto. Por ello, a diferencia del genoma, es un factor a priori modificable, siendo su estudio crucial en materia de Salud Pública. La población del archipiélago canario ha sido estudiada en cuanto a sus niveles de contaminación química, con numerosos estudios de biomonitorización, lo que hace necesario caracterizar el exposoma de ésta y sus consecuencias en términos de enfermedad, para poder implementar medidas correctoras específicas que minimicen el impacto en su salud. METODOS: Se realizó una revisión de la literatura científica (MEDLINE y Scopus) de acuerdo con los criterios PRISMA y siguiendo la metodología PICO, para incluir estudios de biomonitorización de contaminantes, o que evaluaran el efecto de éstos en enfermedades prevalentes en el archipiélago. RESULTADOS: Se seleccionaron veinticinco estudios, tanto de base poblacional como de base hospitalaria. Los resultados demuestran que el exposoma lo conforman, como mínimo, 110 compuestos o elementos, 99 de los cuales parecen estar presentes desde la etapa intrauterina. Destaca la presencia de contaminantes clorados y metales, lo que parece relacionarse con la alta incidencia de enfermedades metabólicas (diabetes), cardiovasculares (hipertensión) y ciertos tipos de neoplasias (cáncer de mama). Aunque tales consecuencias vienen condicionadas por el genoma de la población expuesta, reforzando la enorme importancia de las interacciones genoma-exposoma en el desarrollo de patologías. CONCLUSIONES: Nuestros resultados indican que es necesario establecer medidas correctoras sobre las fuentes de contaminación que modifiquen el exposoma de esta población.

Contaminación química, exposoma y salud en la población de las Islas Canarias: una revisión sistemática de los estudios realizados y análisis de la situación / Chemical pollution, exposome and health in the Canary Islands population: An assessment of the situation

Fundamentos: El conjunto de exposiciones a sustancias químicas y su papel como causa de enfermedad da lugar al conceptode exposoma, conformado parcialmente por contaminantes químicos a los que un individuo se ve expuesto. Por ello, a diferenciadel genoma, es un factora priori modificable, siendo su estudio crucial en materia de Salud Pública. La población del archipiélagocanario ha sido estudiada en cuanto a sus niveles de contaminación química, con numerosos estudios de biomonitorización, lo quehace necesario caracterizar el exposoma de ésta y sus consecuencias en términos de enfermedad, para poder implementar medidascorrectoras específicas que minimicen el impacto en su salud.Métodos: Se realizó una revisión de la literatura científica (MEDLINE yScopus) de acuerdo con los criterios PRISMA y siguiendo lametodología PICO, para incluir estudios de biomonitorización de contaminantes, o que evaluaran el efecto de éstos en enfermedadesprevalentes en el archipiélago.Resultados: Se seleccionaron veinticinco estudios, tanto de base poblacional como de base hospitalaria. Los resultados de-muestran que el exposoma lo conforman, como mínimo, 110 compuestos o elementos, 99 de los cuales parecen estar presentes desdela etapa intrauterina. Destaca la presencia de contaminantes clorados y metales, lo que parece relacionarse con la alta incidencia deenfermedades metabólicas (diabetes), cardiovasculares (hipertensión) y ciertos tipos de neoplasias (cáncer de mama). Aunque talesconsecuencias vienen condicionadas por el genoma de la población expuesta, reforzando la enorme importancia de las interaccionesgenoma-exposoma en el desarrollo de patologías.Concluiones: Nuestros resultados indican que es necesario establecer medidas correctoras sobre las fuentes de contamina-ción que modifiquen el exposoma de esta población.(AU)

Background: The set of exposures to chemical substances and their role as a cause of disease gives rise to the concept of theexposome, partially made up of chemical pollutants to which an individual is exposed, which is why, unlike the genome, it is an a priorimodifiable factor, its study being crucial in terms of Public Health. The population of the Canary Islands has been studied in terms ofits levels of chemical contamination, with numerous biomonitoring studies, which makes it necessary to characterise its exposomeand its consequences in terms of disease, in order to implement specific corrective measures to minimize the impact on its health.Methods: A review of scientific literature (MEDLINE and Scopus) was made, according to PRISMA criteria and PICO methodology, toinclude studies on biomonitoring of pollutants, or evaluating the effect of pollutants on diseases prevalent in the archipelago.Results: Twenty-five studies, both population-based and hospital-based, were selected. The results show that the exposome is madeup of at least 110 compounds or elements, 99 of which appear to be present from the intrauterine stage. The presence of chlorinated po-llutants and metals stands out, which seems to be related to the high incidence of metabolic diseases (diabetes), cardiovascular diseases(hypertension) and certain types of neoplasms (breast cancer). In short, the consequences are conditioned by the genome of the exposedpopulation, reinforcing the enormous importance of genome-exposome interactions in the development of pathologies.Conclusions: Our results indicate that it is necessary to establish corrective measures on the sources of pollution that modifythe exposome of this population.(AU)

Individual blood concentrations of persistent organic pollutants and chemical elements, and COVID-19: A prospective cohort study in Barcelona.

BACKGROUND: There is wide, largely unexplained heterogeneity in immunological and clinical responses to SARS-CoV-2 infection. Numerous environmental chemicals, such as persistent organic pollutants (POPs) and chemical elements (including some metals, essential trace elements, rare earth elements, and minority elements), are immunomodulatory and cause a range of adverse clinical events. There are no prospective studies on the effects of such substances on the incidence of SARS-CoV-2 infection and COVID-19. OBJECTIVE: To investigate the influence of blood concentrations of POPs and elements measured several years before the pandemic on the development of SARS-CoV-2 infection and COVID-19 in individuals from the general population. METHODS: We conducted a prospective cohort study in 154 individuals from the general population of Barcelona. POPs and elements were measured in blood samples collected in 2016-2017. SARS-CoV-2 infection was detected by rRT-PCR in nasopharyngeal swabs and/or by antibody serology using eighteen isotype-antigen combinations measured in blood samples collected in 2020-2021. We analyzed the associations between concentrations of the contaminants and SARS-CoV-2 infection and development of COVID-19, taking into account personal habits and living conditions during the pandemic. RESULTS: Several historically prevalent POPs, as well as arsenic, cadmium, mercury, and zinc, were not associated with COVID-19, nor with SARS-CoV-2 infection. However, DDE (adjusted OR = 5.0 [95% CI: 1.2-21]), lead (3.9 [1.0-15]), thallium (3.4 [1.0-11]), and ruthenium (5.0 [1.8-14]) were associated with COVID-19, as were tantalum, benzo(b)fluoranthene, DDD, and manganese. Thallium (3.8 [1.6-8.9]), and ruthenium (2.9 [1.3-6.7]) were associated with SARS-CoV-2 infection, and so were lead, gold, and (protectively) iron and selenium. We identified mixtures of up to five substances from several chemical groups, with all substances independently associated to the outcomes. CONCLUSIONS: Our results provide the first prospective and population-based evidence of an association between individual concentrations of some contaminants and COVID-19 and SARS-CoV-2 infection. POPs and elements may contribute to explain the heterogeneity in the development of SARS-CoV-2 infection and COVID-19 in the general population. If the associations are confirmed as causal, means are available to mitigate the corresponding risks.

Ethanol and Medical Psychotropics Co-Consumption in European Countries: Results from a Three-Year Retrospective Study of Forensic Samples in Spain.

Ethanol and medical psychotropics (MPs) are legal psychoactive substances widely consumed in Western countries that are routinely detected in standard toxicological analyses at compulsory autopsies, and toxicokinetic interactions between these drugs have been described. However, studies assessing the consequences of this co-consumption are scarce in Europe. We performed a retrospective study on toxicological results from compulsory autopsies in Spain. Thirty-five legal psychotropics, including ethanol, were measured in blood samples from 380 decedents to assess the determinants of such co-consumption. MPs were detected in 42.4% of the subjects. Polypharmacy was frequent in our series (25%), being more frequent in men than in women. More than one-third of the decedents had detectable levels of ethanol, and a significant positive association between ethanol levels and age was evident. About one-third of MPs consumers were also co-consumers of ethanol. The simultaneous consumption of ethanol and MPs was higher in men than in women. Blood alcohol concentrations (BAC) were lower in men who consumed MPs. In polypharmacy deaths, there was a significant negative association between the number of MPs consumed and BAC in men (r = -0.097; p = 0.029). Our results showed a high prevalence of co-consumption of MPs and ethanol in the European population involved in medico-legal issues and suggest that toxicokinetic interactions may be lowering BAC in men. This is a very worrying result, as it could indicate that the legal blood ethanol limits set by legislation would not be appropriate for men on MPs treatment.

Ethanol levels in legally autopsied subjects: Analytical approach and epidemiological relevance in a prospective study in the touristic region of the Canary Islands (Spain).

The aim of this study was to analyze the presence of alcohol in individuals (137) that were subjected to a mandatory medico-legal autopsy in the Institute of Legal Medicine of Las Palmas (Canary Islands, Spain) during 2015. Blood and vitreous humor samples (232) were analyzed by gas chromatography. 46.0% of the individuals were positive for alcohol, being half of them tourists. Blood alcohol concentrations (BAC) was higher in men over 60 years (p = 0.041). 10.2% of the series died in a traffic accident, and victims had the highest proportion of positives to alcohol (64.3%) and the highest BAC (2.56 g/L, p = 0.048). The BAC:VHAC (alcohol in vitreous humor) ratio was higher among victims of traffic crashes (p = 0.036), suggesting a short elapsed interval between the alcohol intake and the fatal accident. The results of this study indicate that ethanol is still heavily involved in non-natural deaths.

Potential Role of Pet Cats As a Sentinel Species for Human Exposure to Flame Retardants.

Flame retardants are a wide group of chemicals used by the industry to avoid combustion of materials. These substances are commonly found in plastics, electronic equipment, fabrics, and in many other everyday articles. Subsequently, ubiquitous environmental contamination by these common chemical is frequently reported. In the present study, we have evaluated the level of exposure to polychlorinated biphenyls (PCBs), brominated diphenyl ethers (BDEs), and organophosphorous flame retardants (OPFRs) in pet cats through the analysis of their serum. We also analyzed the level exposure to such chemicals in a series of 20 cat owners, trying to disclose the role of pet cats as sentinel species of human exposure to FRs. Our results showed that PCBs, banned 40 years ago, showed the lowest levels of exposure, followed by BDEs-banned recently. Congeners PCB-138 and PCB-180 were detected in ≥50% of the series, while BDE-47 was detected in near 90% of the pet cats. On the other hand, the highest levels were that of OPFRs, whose pattern of detection was similar to that observed in humans, thus suggesting a potential role of cats as a sentinel species for human exposure to these currently used FRs. Six out of 11 OPFRs determined [2-ethylhexyldiphenyl phosphate, tributylphosphate, triisobutylphosphate, triphenylphosphate, tris (2-chloroethyl) phosphate, and tris (2-chloroisopropyl) phosphate] were detected in 100% of the samples. It will be interesting to perform future studied aimed to elucidating the potential toxicological effects of these highly detected chemicals both, in cats and humans.

Determinants of increasing serum POPs in a population at high risk for cardiovascular disease. Results from the PREDIMED-CANARIAS study.

Persistent organic pollutants (POPs) are well-known ubiquitous environmental chemicals which have been related to adverse health outcomes, including cardiovascular disease (CVD). The purpose of this study was to evaluate POPs burden, and its determinants, in a population at high risk of suffering CVD enrolled in the PREDIMED Study (Spanish acronym for PREvention by means of MEDiterranean Diet). This cohort was formed by 343 participants (55-80 y.o.), which were selected for a preventive nutritional intervention for CVD based on the Mediterranean Diet. Relevant information on demographic, behavioral, dietary, and socioeconomic characteristics was obtained from each participant through a specific questionnaire, and their anthropometric and clinical measurements were recorded. In addition, the levels of 35 POPs were determined in serum samples taken before the beginning of the nutritional intervention. All the samples showed detectable levels of, at least, one POP, being DDT-derivatives and marker-PCBs the most frequently detected compounds. Our results showed that people at high risk for CVD showed a higher level of contamination by POPs as compared to other studies done in cohorts of Western people at no special risk of CVD. Although educational level seems to be a relevant determinant for POPs burden in our population, the main determining factor seems to be the diet. Thus, while the intake of food of animal origin was significantly associated with levels of PCBs, especially in men, the intake of vegetal-origin food was positively related to levels of organochlorine pesticides, indicating a different dietary source for these two groups of chemicals. Our results showing that subjects at high risk for cardiovascular disease present elevated POPs burden might have a relevant public health impact given the generalized and difficult to avoid exposure to POPs and the elevated worldwide frequency of the CVD.

Consumption of organic meat does not diminish the carcinogenic potential associated with the intake of persistent organic pollutants (POPs).

Numerous studies have shown an epidemiological link between meat consumption and the incidence of cancer, and it has been suggested that this relationship may be motivated by the presence of carcinogenic contaminants on it. Among the most frequently detected contaminants in meat are several types of persistent organic pollutants (POPs), and it is well known that many of them are carcinogenic. On the other hand, an increasing number of consumers choose to feed on what are perceived as healthier foods. Thus, the number of consumers of organic food is growing. However, environmental contamination by POPs is ubiquitous, and it is therefore unlikely that the practices of organic food production are able to prevent this contamination. To test this hypothesis, we acquired 76 samples of meat (beef, chicken, and lamb) of two modes of production (organic and conventional) and quantified their levels of 33 carcinogenic POPs. On this basis, we determined the human meat-related daily dietary exposure to these carcinogens using as a model a population with a high consumption of meat, such as the Spanish population. The maximum allowable meat consumption for this population and the carcinogenic risk quotients associated with the current pattern of consumption were calculated. As expected, no sample was completely free of carcinogenic contaminants, and the differences between organically and conventionally produced meats were minimal. According to these results, the current pattern of meat consumption exceeded the maximum limits, which are set according to the levels of contaminations, and this is associated with a relevant carcinogenic risk. Strikingly, the consumption of organically produced meat does not diminish this carcinogenic risk, but on the contrary, it seems to be even higher, especially that associated with lamb consumption.

Comparative study of the intake of toxic persistent and semi persistent pollutants through the consumption of fish and seafood from two modes of production (wild-caught and farmed).

Adverse effects of chemical contaminants associated with seafood counteract the undoubted benefits for the health of its valuable nutrients. So much so that many dietary guidelines recommend no more than one serving a week of fish and seafood. Although is estimated that aquaculture provides more than 50% of the fish and seafood consumed globally, few research studies have focused in the assessment of the intake of pollutants through aquaculture products. In this study we determined the levels of organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), polycyclic aromatic hydrocarbons (PAHs), and toxic elements (Pb, Cd, Ni, Al, As, and Hg) in a large sample of farmed and wild-caught seafood, and we estimated the intake of these contaminants in two hypothetical models of consumers: those consuming only farmed fish, and those consuming only wild fish. Measured levels of most organic and many inorganic pollutants were higher in aquaculture products, and consequently intake levels if only such products were consumed would be also significantly higher. Thus, the intake of ∑PAHs in adults consuming aquaculture seafood would be 3.30ng/kg-bw/day, and consuming seafood from extractive fishing 2.41ng/kg-bw/day (p<0.05); ∑OCPs, 3.36 vs. 1.85ng/kg-bw/day, respectively (p<0.05); ∑PCBs, 2.35 vs. 2.11ng/kgbw/day, respectively; and the intake of Pb, Ni, As, and Al would be also significantly higher consuming farmed seafood. For children the estimations were very similar, but the difference of intake of PCBs reached statistical significance. The implementation of several decontamination practices in aquaculture would allow not only match the levels of pollution from wild-caught seafood, but also could provide products with much lower levels of pollutants than those, which in turn would allow to increase consumption over the "one serving per week", and so benefit the consumer of the enormous positive health effects of the valuable nutrients of seafood.

The heartworm (Dirofilaria immitis) seems to be able to metabolize organochlorine pesticides and polychlorinated biphenyls: A case-control study in dogs.

It has been described that the co-existence of parasite infection and chemical exposure has various effects on the accumulation of persistent organochlorine pollutants (POPs) in the host. Certain parasites are not only able to accumulate POPs but also seem to have the ability to metabolize certain compounds. We have designed a case-control study aimed to disclose the role of Dirofilaria immitis in the bioavailability of POPs in dogs trying to know whether these parasites store or metabolize the POPs. A total of 40 common POPs (18 polychlorinated biphenyls congeners (PCBs) and 22 organochlorine pesticides were quantified in dog serum. The study included three groups of dogs prospectively recruited in the island of Gran Canaria (Canary Islands, Spain): a) control animals, non-parasitized (serologically tested negative, n=24); b) a group constituted by dogs tested positive for heartworm disease (D. immitis) and negative for other parasites (n=25); and c) the same group of parasitized dogs after the treatment against the parasite (n=25). The presence of D. immitis was strongly associated with lower serum levels of a wide range of pollutant in their hosts (PCB congeners 28, 105, 118, 123, 138, 153, 167 and 180; hexachlorobenzene, lindane, aldrin, dieldrin, and methoxychlor). The serum levels of these substances remained at very low levels after the treatment against the parasite, suggesting that D. immitis do not simply store such compounds, but they probably have some ability to metabolize these pollutants. We encourage the use of the parasite infestation status as a cofactor that needs to be taken into account in studies aimed to evaluate the serum levels of POPs.

Rate of exposure of a sentinel species, invasive American mink (Neovison vison) in Scotland, to anticoagulant rodenticides.

Anticoagulant rodenticides (ARs) are highly toxic compounds that are exclusively used for the control of rodent pests. Despite their defined use, they are nonetheless found in a large number of non-target species indicating widespread penetration of wildlife. Attempts to quantify the scale of problem are complicated by non-random sampling of individuals tested for AR contamination. The American mink (Neovison vison) is a wide ranging, non-native, generalist predator that is subject to wide scale control efforts in the UK. Exposure to eight ARs was determined in 99 mink trapped in NE Scotland, most of which were of known age. A high percentage (79%) of the animals had detectable residues of at least one AR, and more than 50% of the positive animals had two or more ARs. The most frequently detected compound was bromadiolone (75% of all animals tested), followed by difenacoum (53% of all mink), coumatetralyl (22%) and brodifacoum (9%). The probability of mink exposure to ARs increased by 4.5% per month of life, and was 1.7 times higher for mink caught in areas with a high, as opposed to a low, density of farms. The number of AR compounds acquired also increased with age and with farm density. No evidence was found for sexual differences in the concentration and number of ARs. The wide niche and dietary overlap of mink with several native carnivore species, and the fact that American mink are culled for conservation throughout Europe, suggest that this species may act as a sentinel species, and the application of these data to other native carnivores is discussed.

Influence of parasitism in dogs on their serum levels of persistent organochlorine compounds and polycyclic aromatic hydrocarbons.

Persistent organochlorine pollutants (POPs) are toxic chemicals, which accumulate in humans and animals, as only few species have the capability of eliminating them. However, some authors have pointed to the possibility that certain species of invertebrates (i.e. nematodes) could metabolize this type of compounds. As certain species of nematodes act as parasites of vertebrates, this research was designed to explore the influence of some of the most common parasites of the dogs in their serum levels of 56 common POPs. The study included three groups of dogs (n=64), which were prospectively recruited in the island of Gran Canaria (Canary Islands, Spain): a) control animals, non-parasitized (serologically tested negative, n=24); b) dogs tested positive for intestinal parasites and negative for other parasites (n=24); and c) dogs tested positive for heartworm disease (Dirofilaria immitis) and negative for other parasites (n=16). The presence of Dirofilaria immitis was strongly associated with lower serum levels of a wide range of pollutant in their hosts (PCB congeners 28, 52, 118, 138, 153, and 180; hexachlorobenzene, lindane, aldrin, dieldrin, anthracene and pyrene). We also found an inverse association between the hosts' serum levels of PCBs and intestinal parasites. We did not find any association with DDT or its metabolites, but this might be explained by the recently suggested ability of dogs for the efficient metabolization of these compounds. According to the results of this study certain forms of parasitism would reduce the bioavailability of the major classes of POPs in dogs. However, further studies are needed to elucidate whether this phenomenon is due to a competence between parasites and hosts or could respond to a possible capability of parasitic nematodes for the metabolization of these POPs.

Assessment of human health hazards associated with the dietary exposure to organic and inorganic contaminants through the consumption of fishery products in Spain.

In this work we have evaluated the potential carcinogenic and acutely toxic risks associated to the exposure to highly prevalent organic and inorganic contaminants through the consumption of fishery products by the Spanish population. The concentrations of 8 organochlorine pesticides (OCPs), 18 polychlorinated biphenils (PCBs), 7 polycyclic aromatic hydrocarbons (expressed as benzo[a]pyrene toxic equivalents (B[a]Peq)), and three inorganic toxic elements [arsenic (As), cadmium (Cd), and mercury (Hg)] were determined in 93 samples of the most consumed species of white fish, blue fish, cephalopods and seafood species, which were acquired directly in markets and supermarkets in the Canary Islands, Spain. The chemical concentration data were combined with the pattern of consumption of these foodstuffs in order to calculate the daily intake of these contaminants, and on this basis the risk quotients for carcinogenicity and acute toxicity were determined for Spanish adults and children. Our results showed that the daily intake of OCPs, PCBs and B[a]Peq, which is associated to blue fish consumption was the highest within the fish group. The estimated intake of pollutants can be considered low or very low for the individual contaminants, when compared to reference values, except in the case of HCB and As. All the estimated intakes were below the reported Tolerable Daily Intakes. Considering the additive effects of multiple contaminants, the risk of acute toxic effects can also be considered as low or very low. However, our results reflect that the current consumption of white fish in adults and children, and also the blue fish in the case of adults, poses a moderate carcinogenic risk to Spanish consumers, mainly related to their concentrations of As. The conclusions of this research may be useful for the design of appropriate risk communication campaigns.

Validated analytical methodology for the simultaneous determination of a wide range of pesticides in human blood using GC-MS/MS and LC-ESI/MS/MS and its application in two poisoning cases.

Pesticides are frequently responsible for human poisoning and often the information on the involved substance is lacking. The great variety of pesticides that could be responsible for intoxication makes necessary the development of powerful and versatile analytical methodologies, which allows the identification of the unknown toxic substance. Here we developed a methodology for simultaneous identification and quantification in human blood of 109 highly toxic pesticides. The application of this analytical scheme would help in minimizing the cost of this type of chemical identification, maximizing the chances of identifying the pesticide involved. In the methodology that we present here, we use a liquid-liquid extraction, followed by one single purification step, and quantitation of analytes by a combination of liquid and gas chromatography, both coupled to triple quadrupole mass spectrometry, which is operated in the mode of multiple reaction monitoring. The methodology has been fully validated, and its applicability has been demonstrated in two recent cases involving one self-poisoning fatality and one non-fatal homicidal attempt.

In vitro evaluation of oestrogenic/androgenic activity of the serum organochlorine pesticide mixtures previously described in a breast cancer case-control study.

Some organochlorine pesticides (OCs) have been individually linked to breast cancer (BC) because they exert oestrogenic effects on mammary cells. However, humans are environmentally exposed to more or less complex mixtures of these organochlorines, and the biological effects of these mixtures must be elucidated. In this work we evaluated the in vitro effects exerted on human BC cells by the OC mixtures that were most frequently detected in two groups of women who participated in a BC case-control study developed in Spain: healthy women and women diagnosed with BC. The cytotoxicity, oestrogenicity, and androgenicity of the most prevalent OC mixtures found in healthy women (H-mixture) and in BC patients (BC-mixture) were tested at concentrations that resembled those found in the serum of the evaluated women. Our results showed that both OC mixtures presented a similar oestrogenic activity and effect on cell viability, but BC-mixture showed an additional anti-androgenic effect. These results indicate that although the proliferative effect exerted by these mixtures on human breast cells seems to depend mainly on their oestrogenic action, the BC-mixture might additionally induce cell proliferation due to its anti-androgenic activity, therefore increasing the carcinogenic potential of this mixture. The findings of this study demonstrate that subtle variations in the composition of a mixture may induce relevant changes in its biological action.

The assessment of daily dietary intake reveals the existence of a different pattern of bioaccumulation of chlorinated pollutants between domestic dogs and cats.

Pet dogs and cats have been proposed as sentinel species to assess environmental contamination and human exposure to a variety of pollutants, including POPs. However, some authors have reported that dogs but not cats exhibit intriguingly low levels of some of the most commonly detected POPs, such as DDT and its metabolites. This research was designed to explore these differences between dogs and cats. Thus, we first determined the concentrations of 53 persistent and semi-persistent pollutants (16 polycyclic aromatic hydrocarbons (PAHs), 18 polychlorinated biphenyls (PCBs) and 19 organochlorine pesticides (OCPs)) in samples of the most consumed brands of commercial feed for dogs and cats, and we calculated the daily dietary intake of these pollutants in both species. Higher levels of pollutants were found in dog food and our results showed that the median values of intake were about twice higher in dogs than in cats for all the three groups of pollutants (ΣPAHs: 274.8 vs. 141.8; ΣOCPs: 233.1 vs. 83; ΣPCBs: 101.8 vs. 43.8 (ng/kg bw/day); respectively). Additionally, we determined the plasma levels of the same pollutants in 42 and 35 pet dogs and cats, respectively. All these animals lived indoors and were fed on the commercial brands of feed analyzed. As expected (considering the intake), the plasma levels of PAHs were higher in dogs than in cats. However, for organochlorines (OCPs and PCBs) the plasma levels were much higher in cats than in dogs (as much as 23 times higher for DDTs), in spite of the higher intake in dogs. This reveals a lower capacity of bioaccumulation of some pollutants in dogs, which is probably related with higher metabolizing capabilities in this species.

Plasma levels of pollutants are much higher in loggerhead turtle populations from the Adriatic Sea than in those from open waters (Eastern Atlantic Ocean).

In this paper we determined the levels of 63 environmental contaminants, including organic (PCBs, organochlorine pesticides, and PAHs) and inorganic (As, Cd, Cu, Pb, Hg and Zn) compounds in the blood of loggerhead turtles (Caretta caretta) from two comparable populations that inhabit distinct geographic areas: the Adriatic Sea (Mediterranean basin) and the Canary Islands (Eastern Atlantic Ocean). All animals were sampled at the end of a period of rehabilitation in centers of wildlife recovery, before being released back into the wild, so they can be considered to be in good health condition. The dual purpose of this paper is to provide reliable data on the current levels of contamination of this species in these geographic areas, and secondly to compare the results of both populations, as it has been reported that marine biota inhabiting the Mediterranean basin is exposed to much higher pollution levels than that which inhabit in other areas of the planet. According to our results it is found that current levels of contamination by organic compounds are considerably higher in Adriatic turtles than in the Atlantic ones (∑PCBs, 28.45 vs. 1.12ng/ml; ∑OCPs, 1.63 vs. 0.19ng/ml; ∑PAHs, 13.39 vs. 4.91ng/ml; p<0.001 in all cases). This is the first time that levels of PAHs are reported in the Adriatic loggerheads. With respect to inorganic contaminants, although the differences were not as great, the Adriatic turtles appear to have higher levels of some of the most toxic elements such as mercury (5.74 vs. 7.59µg/ml, p<0.01). The results of this study confirm that the concentrations are larger in turtles from the Mediterranean, probably related to the high degree of anthropogenic pressure in this basin, and thus they are more likely to suffer adverse effects related to contaminants.

An estimation of the carcinogenic risk associated with the intake of multiple relevant carcinogens found in meat and charcuterie products.

Numerous epidemiological studies have demonstrated a link between excessive meat consumption and the incidence of various cancers, especially colorectal cancer, and it has been suggested that environmental carcinogens present in meat might be related to the increased risk of cancer associated with this food. However, there are no studies evaluating the carcinogenic potential of meat in relation to its content of carcinogens. Our purpose was to emphasize the relevance of environmental carcinogens existing in meat as a determinant of the association between cancer and meat consumption. Because within Europe, Spain shows high consumption of meat and charcuterie, we performed this study focusing on Spanish population. Based on the preferences of consumers we acquired 100 samples of meat and charcuterie that reflect the variety available in the European market. We quantified in these samples the concentration of 33 chemicals with calculated carcinogenic potential (PAHs, organochlorine pesticides, and dioxin-like PCBs). The carcinogenic risk of these contaminants was assessed for each food using a risk ratio based on the current consumption of meat and charcuterie and the maximum tolerable intake of these foods depending on the level of contamination by the carcinogens they contain. Our results indicate that the current consumption of beef, pork, lamb, chicken, and "chorizo", represents a relevant carcinogenic risk for consumers (carcinogenic risk quotient between 1.33 and 13.98). In order to reduce carcinogenic risk, the study population should halve the monthly consumption of these foods, and also not to surpass the number of 5 servings of beef/pork/chicken (considered together).

Exposure to polycyclic aromatic hydrocarbons (PAHs) and bladder cancer: evaluation from a gene-environment perspective in a hospital-based case-control study in the Canary Islands (Spain).

BACKGROUND: Exposure to polycyclic aromatic hydrocarbons (PAHs) has been linked to bladder cancer. OBJECTIVE: To evaluate the role of PAHs in bladder cancer, PAHs serum levels were measured in patients and controls from a case-control study. METHODS: A total of 140 bladder cancer patients and 206 healthy controls were included in the study. Sixteen PAHs were analyzed from the serum of subjects by gas chromatography-mass spectrometry. RESULTS: Serum PAHs did not appear to be related to bladder cancer risk, although the profile of contamination by PAHs was different between patients and controls: pyrene (Pyr) was solely detected in controls and chrysene (Chry) was exclusively detected in the cases. Phenanthrene (Phe) serum levels were inversely associated with bladder cancer (OR = 0·79, 95%CI = 0·64-0·99, P = 0·030), although this effect disappeared when the allelic distribution of glutathione-S-transferase polymorphisms of the population was introduced into the model (multinomial logistic regression test, P = 0·933). Smoking (OR = 3·62, 95%CI = 1·93-6·79, P<0·0001) and coffee consumption (OR = 1·73, 95%CI = 1·04-2·86, P = 0·033) were relevant risk factors for bladder cancer. CONCLUSIONS: Specific PAH mixtures may play a relevant role in bladder cancer, although such effect seems to be highly modulated by polymorphisms in genes encoding xenobiotic-metabolizing enzymes.