Browsing by Author "Nunes, Luís"
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- Are Chinese consumers at risk due to exposure to metals in crayfish? A bioaccessibility-adjusted probabilistic risk assessmentPublication . Peng, Qian; Nunes, Luís; Greenfield, Ben K.; Dang, Fei; Zhong, HuanFreshwater crayfish, the world's third largest crustacean species, has been reported to accumulate high levels of metals, while the current knowledge of potential risk associated with crayfish consumption lags behind that of finfish. We provide the first estimate of human health risk associated with crayfish (Procambarus clarkii) consumption in China, the world's largest producer and consumer of crayfish. We performed Monte Carlo Simulation on a standard risk model parameterized with local data on metal concentrations, bioaccessibility (phi), crayfish consumption rate, and consumer body mass. Bioaccessibility of metals in crayfish was found to be variable (68-95%) and metal-specific, suggesting a potential influence of metal bioaccessibility on effective metal intake. However, sensitivity analysis suggested risk of metals via crayfish consumption was predominantly explained by consumption rate (explaining >92% of total risk estimate variability), rather than metals concentration, bioaccessibility, or body mass. Mean metal concentrations (As, Cd, Cu, Ni, Pb, Se and Zn) in surveyed crayfish samples from 12 provinces in China conformed to national safety standards. However, risk calculation of phi-modified hazard quotient (HQ) and hazard index (HI) suggested that crayfish metals may pose a health risk for very high rate consumers, with a HI of over 24 for the highest rate consumers. Additionally, the phi-modified increased lifetime risk (ILTR) for carcinogenic effects due to the presence of As was above the acceptable level (10(-5)) for both the median (ILTR = 2.5 x 10(-5)) and 90th percentile (ILTR = 1.8 x 10(-4)), highlighting the relatively high risk of As in crayfish. Our results suggest a need to consider crayfish when assessing human dietary exposure to metals and associated health risks, especially for high crayfish-consuming populations, such as in China, USA and Sweden.
- Arsenic in rice agrosystems (water, soil and rice plants) in Guayas and Los Rios provinces, EcuadorPublication . Otero, X. L.; Tierra, W.; Atiaga, O.; Guanoluisa, D.; Nunes, Luís; Ferreira, T. O.; Ruales, J.Geogenic arsenic (As) can accumulate and reach high concentrations in rice grains, thus representing a potential threat to human health. Ecuador is one of the main consumers of rice in South America. However, there is no information available about the concentrations of As in rice agrosystems, although some water bodies are known to contain high levels of the element. We carried out extensive sampling of water, soil, rice plants and commercial rice (obtained from local markets). Water samples were analysed to determine physico-chemical properties and concentrations of dissolved arsenic. Soil samples were analysed to determine total organic C, texture, total Fe and amorphous Fe oxyhydroxides (Fe-ox), total arsenic (tAs) and the bioavailable fraction (As-Me). The different plant parts were analysed separately to determine total (tAs), inorganic (iAs) and organic arsenic (oAs). Low concentrations of arsenic were found in samples of water (generally <10 mu g I-1) and soil (4.48 +/- 3 mg kg(-1)). The tAs in the rice grains was within the usual range (0.042-0.125 mg kg(-1) dry weight, d.w.) and was significantly lower than in leaves (0.123-0.286 mg kg(-1) d.w.) and stems (0.091-0.201 mg kg(-1) d.w.). The Fe-ox and tAs and also As-Me in flood water were negatively correlated with tAs in the plants. However, the concentrations of As in stems and leaves were linearly correlated with tAs in the soil and flood water. The relationship between tAs and arsenic in the grain fitted a logarithmic function, as did that between tAs in the grain and the stem. The findings seem to indicate that high concentrations of arsenic in the environment (soil or water) or in the rice stem do not necessarily imply accumulation of the element in the grain. The iAs form was dominant (>80%) in all parts of the rice plants. (C) 2016 Elsevier B.V. All rights reserved.
- Assessment of variations in air quality in cities of Ecuador in relation to the lockdown due to the COVID-19 pandemicPublication . Atiaga, Oliva; Guerrero, Fernanda; Páez, Fernando; Castro, Rafael; Collahuazo, Edison; Nunes, Luís; Grijalva, Marcelo; Grijalva, Iván; Otero, Xosé LuisThis study analyzes the effect of lockdown due to COVID-19 on the spatiotemporal variability of ozone (O3), sulfur dioxide (SO2), and nitrogen dioxide (NO2) concentrations in different provinces of continental Ecuador using satellite information from Sentinel - 5P. The statistical analysis includes data from 2018 to March 2021 and was performed based on three periods defined a priori: before, during, and after lockdown due to COVID-19, focusing on the provinces with the highest concentrations of the studied gases (hotspots). The results showed a significant decrease in NO2 concentrations during the COVID-19 lockdown period in all the study areas: the Metropolitan District of Quito (DMQ) and the provinces of Guayas and Santo Domingo de los Ts & PRIME;achilas. In the period after lockdown, NO2 concentrations increased by over 20% when compared to the pre-lockdown period, which may be attributable to a shift towards private transportation due to health concerns. On the other hand, SO2 concentrations during the lockdown period showed irregular, non-significant variations; however, increases were observed in the provinces of Chimborazo, Guayas, Santa Elena, and Morona Santiago, which could be partly attributed to the eruptive activity of the Sangay volcano during 2019-2020. Conversely, O3 concentrations increased by 2-3% in the study areas; this anomalous behavior could be attributed to decreased levels of NOx, which react with ozone, reducing its concentration. Finally, satellite data validation using the corresponding data from monitoring stations in the DMQ showed correlation values of 0.9 for O3 data and 0.7 for NO2 data, while no significant correlation was found for SO2.
- Contamination and carcinogenic risks of lead in lip cosmetics in ChinaPublication . Gong, Yu; Chu, Junru; Kwong, Raymond; Nunes, Luís; Zhao, Di; Tang, Wenli; Li, Chengjiu; Wei, Zhongbo; Ju, Yongming; Li, Hongbo; Ma, Lena Q.; Yu, Xiezhi; Zhong, HuanThere are growing concerns about elevated lead (Pb) levels in lip cosmetics, yet in China, the largest lip cosmetic market, recent Pb contamination in lip cosmetics and associated Pb exposure remain unclear. Here, we measured Pb levels of 29 popular lip cosmetics in China and conducted the bioaccessibility-corrected carcinogenic risk assessments and sensitivity analysis regarding Pb exposure for consumers using Monte Carlo simulation. The Pb concentrations of collected samples ranged from undetectable (< 0.05 mu g/kg) to 0.21 mg/kg, all of which were well below the Pb concentration limit set for cosmetics in China (10 mg/kg). The 50th percentile incremental lifetime cancer risk (ILCR) of Pb in Chinese cosmetics (1.20E-07) was below the acceptable level (1E-06), indicating that the application of lip cosmetics and subsequent Pb exposure does not pose carcinogenic risks to consumers in most cases. The results of this study provide new insights into understanding the Pb risk in lip cosmetics.
- COVID-19 pandemic impacted differently air quality in Latin American citiesPublication . Atiaga, Oliva; Páez, Fernando; Jácome, Wilson; Castro, Rafael; Collaguazo, Edison; Nunes, LuísThis research explores the spatial and temporal variations of nitrogen dioxide (NO2), sulphur dioxide (SO2), and ozone (O-3) levels in four Latin American cities, namely Mexico City, Santiago de Chile, Lima, and the Metropolitan District of Quito, utilizing Sentinel-5P satellite data alongside ground-based monitoring stations. The period covers pre-lockdown, lockdown, and post-lockdown phases of the COVID-19 pandemic, providing insights into pollutant behaviour across different levels of human activity. Findings show notable spatial variability in pollutant levels, with Santiago de Chile repeatedly presenting the highest concentrations of NO2 and SO2, linked to urban development and local weather patterns, whereas Quito showed the lowest levels. The lockdowns typically resulted in decreased NO2 concentrations, yet their effects on SO2 and O-3 levels were inconsistent, highlighting the complexity of pollutant interactions. The research confirms that satellite data serves as an affordable addition to conventional monitoring, especially in areas with limited resources. These results emphasize the necessity for customized, city-oriented strategies to reduce urban air pollution and safeguard public health.
- Ecodesign and environmental assessment: a synergy for higher education institutionsPublication . Swe, Wint; Ribau Teixeira, Margarida; Smuleac, Laura; Nunes, LuísThis article explores how ecodesign can help enhance environmental assessment methods (EAMs) employed by Higher Education Institutions (HEIs). Current EAMs primarily offer resource management evaluations or sustainability rankings but lack holistic and actionable solutions for institutional improvements. The proposed method integrates ecodesign tools, such as Life Cycle Assessments (LCA), environmental benchmarking, and parametric design tools, with existing EAM frameworks. This synergy allows HEIs to quantitatively assess their environmental and social impacts while identifying targeted strategies for improvement. By embedding ecodesign into institutional practices the approach provides a structured pathway to align HEIs with global sustainability goals, fostering innovation and continuous improvement. The paper emphasizes a multi-tool integration strategy, offering a cohesive solution to advance sustainability comprehensively within HEIs.
- Effect of cooking on arsenic concentration in ricePublication . Atiaga, Oliva; Nunes, Luís; Otero, Xosé L.This study assessed the effect of rinsing and boiling on total content of As (tAs) and of its inorganic and organic forms in different types of rice (polished and brown) from Spain and Ecuador. Rice was subjected to five different treatments. The results showed that the treatment consisting of three grain rinsing cycles followed by boiling in excess water showed a significant decrease in tAs content compared with raw rice. Regarding As species, it is worth noting that the different treatments significantly reduced the content of the most toxic forms of As. The estimated lifetime health risks indicate that pre-rinsing alone can reduce the risk by 50%, while combining it with discarding excess water can reduce the risk by 83%; therefore, the latter would be the preferable method.
- Embedded health risk from arsenic in globally traded ricePublication . Nunes, Luís; Li, Gang; Chen, Wei-Qiang; Meharg, Andrew A.; O’Connor, Patrick; Zhu, Yong-GuanInternational food trade is fundamental to globalfood security but with often negative consequences in theproducing country. We propose a method of quantifyingflows ofinorganic arsenic (iAs) and embedded increased lifetime cancerrisks (EHR) at a global scale, where negative impacts are felt onthe importing country. Computations were made for 153countries. Vietnam exports the most iAs embedded in rice (796kg/year) followed by India (788 kg/year), Thailand (485 kg/year),and the United States (323 kg/year). We show that continentalChina, Indonesia, and Malaysia have the highest imports of iAs(292, 174, and 123 kg/year, respectively). Bangladesh rankshighest in EHR followed by Vietnam and Cambodia (150, 141, and 111 per 100,000, respectively). Countries that dependexclusively on imported rice are importing a substantial amount of risk, as, e.g., Kiribati and Solomon Islands (57 and 53 per100,000, respectively). We discuss the potential policy options for reducing population dietary health risks by well-balancedapportioning of rice sources. This study targets policy design solutions based on health gains, rather than on safe levels of the riskfactor alone.
- Evaluation of GRACE data for water resource management in Iberia: a case study of groundwater storage monitoring in the Algarve regionPublication . Neves, Maria C.; Nunes, Luís; Monteiro, José PauloStudy region: Iberia, Algarve basin, South Portugal. Study focus: This study evaluates the performance of several GRACE products in Iberia using the closure of the water budget. Then, it focusses on the Algarve region and explores the potential of GRACE as a tool of quantitative groundwater monitoring capable of bridging gaps in the existing ground-based network. Monthly data from GRACE, ancillary datasets from E-OBS, GLEAM, GRUN and ERA5, and groundwater level measurements from 12 karst-porous aquifers in the Algarve basin (5000 km2) are analyzed from 2004 to 2014. New Hydrological Insights for the Region: When considering the closure of the water budget at the Iberian scale, GRACE Mascon solutions perform remarkably well and better than the products based on spherical harmonics. When considering only the Algarve region, the results are similar to the ones obtained for Iberia, but the GRACE solution that performs the best is the average of the CSR and JPL Mascon products. In spite of the Algarve’s extremely small area when compared to the GRACE footprint, the satellite is capable of capturing the regionally averaged seasonal and deseasonalized variations in observed groundwater storage (correlation between GRACE-derived and regionally averaged ground-based measurements is 0.82). For the first time ever at the regional Algarve scale, bounds are placed on the aquifer’s storage properties which vary from 3.65 × 10 3 to 4.92 × 10 2.
- Global microplastic fiber pollution from domestic laundryPublication . Wang, Chunhui; Song, Jing; Nunes, Luís; Zhao, Hongting; Wang, Peng; Liang, Zhirong; Arp, Hans Peter H.; Li, Gang; Xing, BaoshanThe rapid expansion of fast fashion has significantly increased microplastic fiber (MPF) release during laundry practices, accounting for approximately one-third of primary microplastics entering the ocean. Currently, a significant gap exists in global-scale research on the release of MPFs from washing textiles. This study introduces an innovative empirical model to assess the spatial distribution of MPF emissions. The model estimates an annual global emission of 5.69 million tons of MPFs from laundry. Of this total, machine washing accounts for the majority (93.7 %), with hand washing contributing the remaining 6.3 %. As the primary source of MPF pollution, Asia's ' s emissions reach 3.71 million tons, far exceeding those of North America (1.18 million tons) and Europe (0.45 million tons). The primary issue is that wastewater management efficiency varies significantly worldwide. In Asia, there is persistently high discharge of MPFs into natural waters, and the removal efficiency of wastewater treatment plants is still comparatively low. In contrast, the United States and many European countries exhibit better MPF retention. The global nature of this challenge mandates international collaboration for comprehensive environmental conservation. Our study provides the first high-resolution global distribution map of MPF emissions and discharge into natural waters, establishing a data foundation for global and regional management of microplastics originating from household laundry sources.
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