Domestic or imported? An assessment of carbon footprints and sustainability of seafood consumed in Australia

The distance between where food is produced and consumed is increasing, and is often taken as evidence of an unsustainable global food system. Seafood is a highly traded commodity yet seafood sustainability assessments do not typically consider the impacts of the movement of products beyond the fishery or farm. Here we use life cycle assessment to examine the carbon footprint of the production and distribution of select seafood products that are consumed in Australia and determine differences in the sustainability of imports and their domestically produced counterparts. We found that the distance food is transported is not the main determinant of food sustainability. Despite the increased distance between production and consumption, carbon footprints of meals from imported seafood are similar to meals consisting of domestically produced seafood, and sometimes lower, depending on the seafood consumed. In combining LCA with existing seafood sustainability criteria the trade-offs between sustainability targets become more apparent. Carbon ‘footprinting’ is one metric that can be incorporated in assessments of sustainability, thereby demonstrating a broader perspective of the environmental cost of food production and consumption.     

Why are Prices in Wild Catch and Aquaculture Industries so Different?

Through a comparative analysis of prices in capture fisheries and aquaculture sectors, the objectives of this paper are a) to investigate three the trends in prices of forage catches to feed the aquaculture species, b) to analyze the amount of fish species need to feed aquaculture species in order to assess the level of efficiency in resource use, and c) to examine the degree of economic concentration either in wild-catch industry and aquaculture sectors. The results show that prices of cultivated species are higher than prices of the same species when harvested from the sea. We explain this fact by the interplay of three forces. First, the amount of wild fish to feed aquaculture species continues to improve over time. Second, the pressure of fishing activities has not been reduced since catches of most forage fishes are declining, which induce higher prices of capture species that feed aquaculture production. Third, the level of seafood market concentration is significantly higher in aquaculture than in wild catches, which generates higher prices in aquaculture.     

Estimate of the uncertainty in measurement for the determination of mercury in seafood by TDA AAS

An approach for the estimate of the uncertainty in measurement considering the individual sources related to the different steps of the method under evaluation as well as the uncertainties estimated from the validation data for the determination of mercury in seafood by using thermal decomposition/amalgamation atomic absorption spectrometry (TDA AAS) is proposed. The considered method has been fully optimized and validated in an official laboratory of the Ministry of Agriculture, Livestock and Food Supply of Brazil, in order to comply with national and international food regulations and quality assurance. The referred method has been accredited under the ISO/IEC 17025 norm since 2010. The approach of the present work in order to reach the aim of estimating of the uncertainty in measurement was based on six sources of uncertainty for mercury determination in seafood by TDA AAS, following the validation process, which were: Linear least square regression, Repeatability, Intermediate precision, Correction factor of the analytical curve, Sample mass, and Standard reference solution. Those that most influenced the uncertainty in measurement were sample weight, repeatability, intermediate precision and calibration curve. The obtained result for the estimate of uncertainty in measurement in the present work reached a value of 13.39%, which complies with the European Regulation EC 836/2011. This figure represents a very realistic estimate of the routine conditions, since it fairly encompasses the dispersion obtained from the value attributed to the sample and the value measured by the laboratory analysts. From this outcome, it is possible to infer that the validation data (based on calibration curve, recovery and precision), together with the variation on sample mass, can offer a proper estimate of uncertainty in measurement.     

Using DNA barcoding to track seafood mislabeling in Los Angeles restaurants

Seafood mislabeling is common in both domestic and international markets. Studies on seafood fraud often report high rates of mislabeling (e.g., >70%), but these studies have been limited to a single sampling year, which means it is difficult to assess the impact of stricter governmental truth‐in‐labeling regulations. We used DNA barcoding to assess seafood labeling in 26 sushi restaurants in Los Angeles over 4 years. Seafood from 3 high‐end grocery stores were also sampled (n = 16) in 2014. We ordered 9 common sushi fish from menus, preserved tissue samples in 95% ethanol, extracted the genomic DNA, amplified and sequenced a portion of the mtDNA COI gene, and identified the resulting sequence to known fish sequences from the National Center for Biotechnology Information nucleotide database. We compared DNA results with the U.S. Food and Drug Administration (FDA) list of acceptable market names and retail names. We considered sushi‐sample labels that were inconsistent with FDA names mislabeled. Sushi restaurants had a consistently high percentage of mislabeling (47%; 151 of 323) from 2012 to 2015, yet mislabeling was not homogenous across species. Halibut, red snapper, yellowfin tuna, and yellowtail had consistently high (<77%) occurrences of mislabeling on menus, whereas mislabeling of salmon and mackerel were typically low (>15%). All sampled sushi restaurants had at least one case of mislabeling. Mislabeling of sushi‐grade fish from high‐end grocery stores was also identified in red snapper, yellowfin tuna, and yellowtail, but at a slightly lower frequency (42%) than sushi restaurants. Despite increased regulatory measures and media attention, we found seafood mislabeling continues to be prevalent.     

原子荧光法同时测定海产品中砷、汞

文章以青岛团岛农贸市场的新鲜鱼、虾、贝类为研究对象,采用微波消解氢化物发生-原子荧光法同时测定海产品中的砷、汞含量,结果表明该方法具有很好的准确度和精密度可以用于海产品中砷、汞的快速测定。应用生物质量指数法,参照国家海洋局海洋生物质量评价标准和农业部行业标准无公害食品水产品中有毒有害物质限量进行质量评价。     

食品中砷和硒生物可给性研究及健康风险/有益性评价

硒(Se)是人体必需的微量元素,一般通过大米和海鲜摄入。然而大米和海鲜是人体砷(As)暴露的主要途径之一。采用ICP-MS对广州市售的大米和3种鱼中砷和硒浓度进行了检测,并通过体外(in vitro)模拟胃肠消化(PBET)法对鱼肉中砷和硒的生物可给性进行了考察。结果表明,大米和鱼肉中砷的浓度分别为0.085～0.168μg·g~(-1)和2.224～5.533μg·g~(-1),硒的浓度分别为0.098～0.190μg·g~(-1)和1.641～2.315μg·g~(-1)。大米和鱼肉中86.86%～99.34%和51.95%～75.64%的砷生物可给,76.73%～85.44%和71.48%～79.83%的硒生物可给。通过大米和鱼肉摄入的硒基本可以满足人体需求。通过大米和3种鱼摄入的无机砷占国际粮农组织和世界卫生组织(FAO/WHO)公布的无机砷的每日最高允许摄入量(TWI)2.1μg·kg~(-1)BW的0.5%～35.7%,但是摄入无机砷的致癌风险分别为1.69×10~(-5)～5.81×10~(-4)和2.13×10~(-4)～7.34×10~(-4),是可接受或可容忍的风险的0.17～7.3倍,尤其是小孩,更易摄入砷产生毒害。     

Can household consumers save the wild fish? Lessons from a sustainable seafood advisory

Conservation organizations seeking to reduce over-fishing and promote better fishing practices have increasingly turned to market-based mechanisms such as environmental sustainability labels (eco-labels) in order to shift patterns of household consumption. This paper presents an analysis of consumer response to an advisory for sustainable seafood adopted by a regional supermarket in the United States. The advisory consisted of a label in which one of three traffic light colors was placed on each fresh seafood product to inform consumers about its relative environmental sustainability. Green meant “best” choice, yellow meant “proceed with caution,” and red meant “worst choice”. Using a unique product-level panel scanner data set of weekly sales and taking advantage of the random phase-in of the advisory by the retailer, we apply a difference-in-differences identification strategy to estimate the effect of the advisory on overall seafood sales as well as the heterogeneous impact of the advisory by label color and whether the seafood met additional health-related criteria. We find evidence that the advisory led to a statistically significant 15.3% decline in overall seafood sales, a statistically significant 34.9% decline in the sale of yellow labeled seafood, and a statistically significant 41.3% decline in the sale of yellow labeled seafood on a mercury safe list. We find no statistically significant difference in sales of green or red labeled seafood.     

广州市居民食品砷摄入的健康风险评价

从暴露途径来看,食物是人体砷暴露的主要途径之一。从饮食结构来看,广州市居民膳食主要来源于谷类食品,同时鱼虾类总体平均摄入量约为全国总体平均摄入量的2倍。因此,在分析广州市市场大米和海鲜这2种典型食品中砷含量的基础上对广州市居民食品砷摄入的健康风险进行了评价。分析了广州市场上的26种不同品牌的大米中的总砷含量,其含量范围为0.082～0.171μg·g~(-1),平均浓度为(0.127±0.027)μg·g~(-1),满足绿色食品大米标准(≤0.40μg·g~(-1))。在14种鱼虾蟹贝类海鲜中的砷含量分析基础上,计算得出广州市场上鱼类中总砷的平均含量为0.488μg·g~(-1),虾蟹贝类中总砷的平均含量为3.44μg·g~(-1),相比较国内外,广州市场鱼虾蟹中砷的含量整体处于中间水平。最后综合文献调研中其他主要食品中砷的含量,计算得出广州市成人通过食品每日摄入总砷的量为5.08μg·kg~(-1)BW·d~(-1)。建议日常饮食需要特别控制每日海鲜的摄入量,尤其是砷含量较高的濑尿虾、红虾及红蟹、花蟹。