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Hemp cultivation is living a period of renewed interest worldwide after long years of opposition and abandonment. The European Union (EU) allows and subsidizes the growing of fiber and oilseed cultivars of Cannabis sativa L. with respect to the THC content limit of 0.2%. The EU method for the quantitative determination of Δ9-tetrahydrocannabinol (THC) content in hemp varieties provides to apply a tolerance of 0.03 g of THC per 100 g of sample concerning compliance assessment to that limit. However, the method does not report any precision data, especially useful as a function of THC content to evaluate measurement uncertainty and therefore to establish the conformity of hemp at different THC legal limits. Measurement uncertainty of the method by both bottom-up and top-down approach, besides repeatability and reproducibility, was investigated and estimated in the THC concentration range 0.2–1.0%, which includes the different legal limits set out for hemp around the world. We proposed Decision Rules for conformity of hemp showing that a non-compliant declaration beyond reasonable doubt should be stated when the THC content, as a mean result on a duplicate analysis, exceeds the limit by at least 11–15%, depending on THC limit. We highlighted other issues concerning practical aspects of hemp analysis, from sampling to evaluation of results, as well as the need to carry out collaborative studies on the EU method. [ABSTRACT FROM AUTHOR]

With the International Maritime Organization's (IMO) International Convention for the Control and Management of Ships' Ballast Water and Sediments now in force, determining abundance and distribution of phytoplankton inside ballast tanks is critical for successful ballast water management, particularly when assessing compliance. The relationship between the abundance and distribution of cells was examined to obtain the best representative sample of the entire phytoplankton community in ballast tanks, comparing three ballast water sampling techniques including in-line, in-tank, and Van Dorn bottle methods. Lloyd's index, Dy, and Gini index were applied to compare methods of sample collection and determine representativeness of samples and performance of sampling methods. Phytoplankton abundance trends from live microscopy counts using fluorescein diacetate (FDA) were also compared to those using a FlowCAM on preserved samples. The phytoplankton community showed a patchy distribution inside the ballast tank and this trend was observed across all voyages. The estimated marginal mean analysis showed that in hypothetical conditions (e.g., 702 m3 of water in ballast tank and phytoplankton whole-tank abundance of 19,522 cells), the difference among the three methods was small. Conversely, statistical analysis performed on empiric abundances using a negative binomial regression model determined that the volume discharged during sampling of ballast water has an effect on the number of cells collected on a given voyage. Results of this study also confirmed that the in-line method may be a better method at collecting phytoplankton samples from ballast tanks than the in-tank or Van Dorn method, regardless of the time at which samples are collected. Finally, the number of living cells and the number of preserved cells showed similar trends for most of the voyages, despite fewer samples analyzed using FDA. [ABSTRACT FROM AUTHOR]

This study determines the levels of compliance of European fresh waters with a bioavailability-based copper Environmental Quality Standard (EQS). A tiered approach for compliance assessment is used at which the first tier compares the dissolved metal concentration to a threshold, estimated using either regional or continental water chemistry data. At the second tier, the bioavailable metal concentration is calculated using the chemistry of the water body, and compared to the EQSbioavailable for copper. The thresholds at Tier 1 must be set at a level to ensure adequate protection of sensitive environments and to ensure efficient use of regulatory resources. Compliance of 99.3% is observed where bioavailability-based thresholds are used for the implementation derived from regionally relevant water chemistry data. Sites where elevated ambient background levels of copper are combined with high bioavailability (waters with low dissolved organic carbon) are those most likely to be at risk from copper exposures. [ABSTRACT FROM AUTHOR]

We use basic characteristics of statistical significance test to argue the abandonment of hypothesis testing in environmental standard (or criterion) compliance assessment. The typical sample size used for environmental assessment is small, and the natural variation of many water quality constituent concentrations is high. These conditions lead to low statistical power of the hypothesis tests used in the assessment process. As a result, using hypothesis testing is often inefficient in detecting noncompliance. When a noncompliance is detected, it is frequently due to sampling or other types of error. We illustrate the problems using two examples, through which we argue that these problems cannot be resolved under the current practice of assessing compliance one water at a time. We recommend that the hypothesis testing framework be replaced by a statistical estimation approach, which can more effectively leverage information from assessments on similar waters using a probabilistic assessment approach. [ABSTRACT FROM AUTHOR]

An indicative compliance assessment of the Europe-wide bioavailable lead Environmental Quality Standard of 1.2 µg L (EQS) was undertaken against regulatory freshwater monitoring data from six European member states and FOREGS database. Bio-met, a user-friendly tool based upon Biotic Ligand Models (BLMs) was used to account for bioavailability, along with the current European Water Framework Directive lead dissolved organic carbon correction approach. The outputs from both approaches were compared to the BLM. Of the 9054 freshwater samples assessed only 0.6% exceeded the EQS of 1.2 µg L after accounting for bioavailability. The data showed that ambient background concentrations of lead across Europe are unlikely to influence general compliance with the EQS, although there may be isolated local issues. The waters showing the greatest sensitivity to potential lead exposures are characterized by relatively low DOC (< 0.5 mg L), regardless of the pH and calcium concentrations. [ABSTRACT FROM AUTHOR]

Fuel adulteration and cross-contamination lead to low-quality fuel products, which may cause increased environmental pollution, loss of taxes and engine problems. An establishment of a quality monitoring mechanism based on laboratory measurements may reveal problematic areas of the fuel supply chain. For the purposes of this work, 97 unleaded petrol samples were measured in order to quantify mass concentration of quinizarin, a substance used in Greece to easily mark the presence of 95 Research Octane Number unleaded petrol in other types of automotive fuels. The samples were obtained from petroleum retail stations selling different brands of fuels and located in different geographic regions of Greece. Statistical analysis of the results revealed quinizarin mass concentrations below the 3 mg L legislation specification limit and significant differences between brands and geographic regions, which may attributed to the structure of the fuel supply chain in Greece in combination with quinizarin properties and way of handling. Moreover, certain approaches were used for the calculation of decision limits for assessing compliance or non-compliance. These approaches take measurement reproducibility or estimated in-house uncertainty into account, in order to minimize the probability of false rejection. [ABSTRACT FROM AUTHOR]

A numerical water quality criterion in the U.S. consists of three components representing magnitude, duration, and frequency. While magnitude and duration are well defined and conceptually unambiguous, the meaning of the frequency component is often debatable. We interpret the frequency component as a tool for accounting for uncertainty in estimating the mean concentration of a water quality constituent, after revisiting early works on environmental standards and criteria. Based on this interpretation, we illustrate management-related issues when using the default frequency of one exceedance in 3 years in compliance assessment. We propose a data-driven approach for estimating an appropriate frequency to ensure a consistent level of confidence in a water's compliance of a water quality criterion. The data-driven frequency is determined by water quality constituent concentration distribution characteristics and sample size. The method is illustrated using two examples. [ABSTRACT FROM AUTHOR]

Facilitating compliance management, that is, assisting a company’s management in conforming to laws, regulations, standards, contracts, and policies, is a hot but non-trivial task. The service-oriented architecture (SOA) has evolved traditional, manual business practices into modern, service-based IT practices that ease part of the problem: the systematic definition and execution of business processes. This, in turn, facilitates the online monitoring of system behaviors and the enforcement of allowed behaviors—all ingredients that can be used to assist compliance management on the fly during process execution. In this paper, instead of focusing on monitoring and runtime enforcement of rules or constraints, we strive for an alternative approach to compliance management in SOAs that aims at assessing and improving compliance. We propose two ingredients: (i) a model and tool to design compliant service-based processes and to instrument them in order to generate evidence of how they are executed and (ii) a reporting and analysis suite to create awareness of a company’s compliance state and to enable understanding why and where compliance violations have occurred. Together, these ingredients result in an approach that is close to how the real stakeholders—compliance experts and auditors—actually assess the state of compliance in practice and that is less intrusive than enforcing compliance. [ABSTRACT FROM AUTHOR]

Frequently, the ultimate goal of an analytical measurement is to assess compliance in respect to a specification limit. So, the necessary requirement is to make a correct decision on the grounds of the measurement result. It is suggested a practical methodology to attain fitness for purpose results when specification limits are established for compliance assessment. It is based on a comparison between fitness for purpose uncertainty functions that define a high probability of conclusive correct decisions and a characteristic uncertainty function which describes the performance of the analytical system along concentration in a given condition of measurement. To attain fitness for purpose results, different replication programs are applied. Determinations of Zn, Mn and Cd in potable water are discussed as case studies. They represent different cases concerning relative position of detection and specification limits. A definition of fitness for purpose when specification limits are relevant is given. Quality of analytical results and analytical procedures should be associated with the concept of fitness for purpose. [ABSTRACT FROM AUTHOR]

Background: The European Water Framework Directive (WFD) requires the monitoring of biota—preferably fish—to check the compliance of tissue concentrations of priority substances (PS) against substance-specific environmental quality standards (EQSs). In monitoring programs, different fish species are covered, which often are secondary consumers with a trophic level (TL) of about 3. For harmonization, a normalization of monitoring data to a common trophic level is proposed, i.e., TL 4 (predatory fish) in freshwaters, so that data would be sufficiently protective. For normalization, the biomagnification properties of the chemicals can be considered by applying substance-specific trophic magnification factors (TMFs). Alternatively, TL-corrected biomagnification factors (BMFTLs) may be applied. Since it is impractical to derive site-specific TMFs or BMFTLs, often data from literature will be used for normalization. However, available literature values for TMFs and BMFTLs are quite varying. In the present study, the use of literature-derived TMFs and BMFTLs in data normalization is studied more closely. Results: An extensive literature evaluation was conducted to identify appropriate TMFs for the WFD PS polybrominated diphenyl ethers (PBDE), hexachlorobenzene, perfluorooctane sulfonate (PFOS), dioxins and dioxin-like compounds (PCDD/F + dl-PCB), hexabromocyclododecane, and mercury. The TMFs eventually derived were applied to PS monitoring data sets of fish from different trophic levels (chub, bream, roach, and perch) from two German rivers. For comparison, PFOS and PBDE data were also normalized using literature-retrieved BMFTLs. Conclusions: The evaluation illustrates that published TMFs and BMFTLs for WFD PS are quite variable and the selection of appropriate values for TL 4 normalization can be challenging. The normalized concentrations partly included large uncertainties when considering the range of selected TMFs, but indicated whether an EQS exceedance at TL 4 can be expected. Normalization of the fish monitoring data revealed that levels of substances accumulating in the food web (TMF or BMF > 1) can be underestimated when relying on fish with TL < 4 for EQS compliance assessment. The evaluation also revealed that TMF specifically derived for freshwater ecosystems in Europe would be advantageous. Field-derived BMFTLs seemed to be no appropriate alternative to TMFs, because they can vary even stronger than TMFs. [ABSTRACT FROM AUTHOR]