Monitoring the Health of Coastal Environments in the Pacific Region-A Review.

Coastal areas provide important ecological services to populations accessing, for example, tourism services, fisheries, minerals and petroleum. Coastal zones worldwide are exposed to multiple stressors that threaten the sustainability of receiving environments. Assessing the health of these valuable ecosystems remains a top priority for environmental managers to ensure the key stressor sources are identified and their impacts minimized. The objective of this review was to provide an overview of current coastal environmental monitoring frameworks in the Asia-Pacific region. This large geographical area includes many countries with a range of climate types, population densities and land uses. Traditionally, environmental monitoring frameworks have been based on chemical criteria set against guideline threshold levels. However, regulatory organizations are increasingly promoting the incorporation of biological effects-based data in their decision-making processes. Using a range of examples drawn from across the region, we provide a synthesis of the major approaches currently being applied to examine coastal health in China, Japan, Australia and New Zealand. In addition, we discuss some of the challenges and investigate potential solutions for improving traditional lines of evidence, including the coordination of regional monitoring programs, the implementation of ecosystem-based management and the inclusion of indigenous knowledge and participatory processes in decision-making.

Plastic additives: challenges in ecotox hazard assessment.

The risk of plastic debris, and specifically micro(nano)plastic particles, to ecosystems remains to be fully characterized. One particular issue that warrants further characterization is the hazards associated with chemical additives within micro(nano)plastic as they are not chemically bound within the polymers and can be persistent and biologically active. Most plastics contain additives and are therefore potential vectors for the introduction of these chemicals into the environment as they leach from plastic, a process that can be accelerated through degradation and weathering processes. There are knowledge gaps on the ecotoxicological effects of plastic additives and how they are released from parent plastic materials as they progressively fragment from the meso to micro and nano scale. This review summarizes the current state of knowledge of the ecotoxicity of plastic additives and identifies research needs to characterize the hazard they present to exposed biota. The potential ecological risk of chemical additives is of international concern so key differences in governance between the European Union and New Zealand to appropriately characterize their risk are highlighted.

Assessment of the ecotoxicity of urban estuarine sediment using benthic and pelagic copepod bioassays.

Urban estuarine sediments are sinks to a range of contaminants of anthropogenic origin, and a key challenge is to characterize the risk of these compounds to receiving environments. In this study, the toxicity of urban estuarine sediments was tested using acute and chronic bioassays in the benthic harpacticoid Quinquelaophonte sp., and in the planktonic calanoid Gladioferens pectinatus, two New Zealand copepod species. The sediment samples from the estuary tributary sites significantly impacted reproduction in Quinquelaophonte sp. However, results from one of the estuary sites were not significantly different to those from the tributaries sites, suggesting that chemicals other than trace metals, polycyclic aromatic hydrocarbons and ammonia may be the causative stressors. Sediment elutriate samples had significant effects on reproductive endpoints in G. pectinatus, and on the induction of DNA damage in cells, as shown by the comet assay. The results indicate that sediment contamination at the Ahuriri Estuary has the potential to impact biological processes of benthic and pelagic organisms. The approach used provides a standardized methodology to assess the toxicity of estuarine sediments.

Assessment of endocrine disruption and oxidative potential of bisphenol-A, triclosan, nonylphenol, diethylhexyl phthalate, galaxolide, and carbamazepine, common contaminants of municipal biosolids.

The use of biosolids as a soil conditioner and fertiliser is hindered by the limited knowledge on the risks of micro-contaminants they contain. This study investigated the binding of six organic contaminants commonly found in biosolids, to the estrogen (ER), androgen (AR), aryl hydrocarbon (AhR), and transthyretin (TTR) receptors and their redox activity. Triclosan (TCS), bisphenol-A (BPA), and technical nonylphenol (TNP) had affinity for the TTR with relative potencies of 0.3, 0.03, and 0.076 respectively. Further, binding to TTR was the only toxicological response observed for carbamazepine, which induced sub-maximal response and relative potency of 0.0017. Estrogenic activity was induced by BPA, galaxolide (HHCB), diethylhexyl phthalate (DEHP) and TNP with BPA having the strongest potency of 5.1 × 10-6 relative to estradiol. Only BPA showed androgenic activity but it was not quantifiable. BPA also showed anti-androgenic activity along with TCS, HHCB, and TNP in the order of TNP > HHCB > TCS ~ BPA (relative potencies 0.126, 0.042, 0.032, 0.03). No compounds exhibited anti-estrogenic or AhR activity, or were redox-active in the dithiothreitol assay. The results highlight the multiple modes of action through which these compounds may impact exposed organisms, and the concentrations at which effects may occur. This allows assessment of the likelihood of effects being observed at environmental concentrations, and the potential contribution of these compounds.

Assessment of urban stream sediment pollutants entering estuaries using chemical analysis and multiple bioassays to characterise biological activities.

Stormwater contaminants are a major source of often neglected environmental stressors because of the emphasis placed on the management of municipal and industrial wastewaters. Stormwater-derived pollutants in sediments from two New Zealand estuaries was characterised by analytical chemistry and bioassays. Contaminants were extracted from sediment using accelerated solvent extraction (ASE), recovered and concentrated by solid phase extraction (SPE), and analysed for polycyclic aromatic hydrocarbons (PAHs), selected metals, and musk fragrances. The concentrations of PAHs were below the ANZECC Interim Sediment Quality Guideline values while those of lead and zinc exceeded them in some samples. The sediment extracts containing organic contaminants exhibited acute toxicity in the zebrafish fish embryo toxicity (FET) and teratogenicity, induction of biotransformation (EROD activity), and genotoxicity (comet assay) in zebrafish. The potential of the extracts to interact with endocrine signalling processes was assessed by GeneBLAzer reporter gene bioassays and they exhibited estrogenic, androgenic, and anti-progestagenic activities.

Assessment of cytotoxicity, genotoxicity and 7-ethoxyresorufin-O-deethylase (EROD) induction in sediment extracts from New Zealand urban estuaries.

Sediments represent a major sink for contaminants resulting from industrial and agricultural activities - especially lipophilic substances. This study exclusively used in vitro methodologies to characterize specific toxicity effects of contaminants in sediment extracts from two urban New Zealand estuaries. Sediment extracts were prepared and tested for a range of biological endpoints. The micronucleus and comet assays in V79 cells were used to assess genotoxicity. Induction of 7-ethoxyresorufin-O-deethylase in piscine RTL-W1 cells was determined to estimate dioxin-like toxicity. Cytotoxic potentials were analyzed by neutral red uptake and MTT reduction. There was evidence of strong dioxin-like toxicity and moderate cytotoxicity. Genotoxicity was distinct in the micronucleus assay, but low in the comet assay. The results indicate the presence of chemicals in the sediments with the potential to pose a risk through multiple mechanisms of toxicity, the identities and amounts of which will be disclosed in a parallel study alongside with in vivo toxicity data.

An assessment of endocrine activity in Australian rivers using chemical and in vitro analyses.

Studies on endocrine disruption in Australia have mainly focused on wastewater effluents. Limited knowledge exists regarding the relative contribution of different potential sources of endocrine active compounds (EACs) to the aquatic environment (e.g., pesticide run-off, animal farming operations, urban stormwater, industrial inputs). In this study, 73 river sites across mainland Australia were sampled quarterly for 1 year. Concentrations of 14 known EACs including natural and synthetic hormones and industrial compounds were quantified by chemical analysis. EACs were detected in 88 % of samples (250 of 285) with limits of quantification (LOQ) ranging from 0.05 to 20 ng/l. Bisphenol A (BPA; LOQ = 20 ng/l) was the most frequently detected EAC (66 %) and its predicted no-effect concentration (PNEC) was exceeded 24 times. The most common hormone was estrone, detected in 28 % of samples (LOQ = 1 ng/l), and the PNEC was also exceeded 24 times. 17α-Ethinylestradiol (LOQ = 0.05 ng/l) was detected in 10 % of samples at concentrations ranging from 0.05 to 0.17 ng/l. It was detected in many samples with no wastewater influence, and the PNEC was exceeded 13 times. In parallel to the chemical analysis, endocrine activity was assessed using a battery of CALUX bioassays. Estrogenic activity was detected in 19 % (53 of 285) of samples (LOQ = 0.1 ng/l 17ß-estradiol equivalent; EEQ). Seven samples exhibited estrogenic activity (1-6.5 ng/l EEQ) greater than the PNEC for 17ß-estradiol. Anti-progestagenic activity was detected in 16 % of samples (LOQ = 8 ng/l mifepristone equivalents; MifEQ), but the causative compounds are unknown. With several compounds and endocrine activity exceeding PNEC values, there is potential risk to the Australian freshwater ecosystems.

Cumulative impacts assessment along a large river, using brown bullhead catfish (Ameiurus nebulosus) populations.

The effects of point-source and diffuse discharges on resident populations of brown bullhead catfish (Ameiurus nebulosus (LeSueur, 1819)) in the Waikato River (New Zealand) were assessed at sites both upstream and downstream of point-source discharges. At each site, the population parameters, relative abundance, age structure, and individual indices, such as condition factor, organ (gonad, liver, and spleen) to somatic weight ratios, and number and size of follicles per female, were assessed. Physiological (blood), biochemical (hepatic ethoxyresorufin-O-deethylase [EROD] and plasma steroids), and other indicators (bile chemistry and liver metals) of exposure or response also were measured. No impacts on brown bullhead health were obvious at individual geothermal, municipal sewage, or thermal discharge sites or cumulatively along the river. Brown bullhead from the bleached kraft mill effluent site showed elevated levels of EROD, decreased numbers of red blood cells, increased numbers of white blood cells, and depressed levels of sex steroids. However, growth rates, condition factor, age structure, and gonadosomatic index suggest that discharges with significant heat or nutrients benefit catfish despite physiological impairment at one site. Consideration of brown bullhead population-level responses to discharges in a monitoring framework revealed three different population-level response patterns resulting from the point-source discharges.