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Knutson S.,University of Hawaii at Manoa | Downs C.A.,Haereticus Environmental Laboratory | Richmond R.H.,Kewalo Marine Laboratory
Ecotoxicology | Year: 2012

This study examined concentrations of Irgarol 1051® in selected marinas on the island of Oahu, Hawaii and used laboratory bioassays to assess effects of Irgarol on coral larval settlement. Field surveys of small boat marinas performed in 2006-2007 revealed low concentrations of Irgarol 1051®, an antifouling paint additive, ranging from non-detected (<17 ng/l) to 283 ng/l. The highest concentrations of Irgarol 1051® were found in marinas with low flushing rates and a high density of moored boats and boat traffic. The potential effect of Irgarol 1051® on coral larval settlement was evaluated in the laboratory using planulae from Porites hawaiiensis, a zooxanthellate shade-dwelling coral found in Hawaiian waters. Exposure to Irgarol 1051® at 100 ng/l resulted in a statistically significant reduction in settlement of coral larvae. This was within the range of Irgarol 1051® concentrations found in some of the marinas surveyed on the island of Oahu but Irgarol was not detected in seawater samples at offshore reefs. © 2011 Springer Science+Business Media, LLC.

Hamlin H.J.,University of Maine, United States | Marciano K.,University of Maine, United States | Downs C.A.,Haereticus Environmental Laboratory
Chemosphere | Year: 2015

Nonylphenol (NP) is a non-ionic surfactant used extensively in industrial applications, personal care products, and many plastics. We exposed marine orchid dottybacks (Pseudochromis fridmani) for 48h to either glass, Teflon, or two bags labeled as FDA food-grade polyethylene (PE1 and PE2) from different manufacturers. The PE2 bags leached high levels of NP into the contact water, which were taken up by the fish, and decreased short and long-term survival. Concentrations of NP that leached from the bags were consistent with 96h LC50 values determined in this study, indicating NP is the likely toxic agent. Despite being similarly labeled, the NP concentrations that leached from the bags and the resultant toxicity to the fish varied dramatically between manufacturers. This study highlights that some plastics, labeled as food-safe, can be highly toxic to aquatic animals, and could pose a greater threat to humans than previously realized. This study also highlights risks for aquatic animals exposed to increasing quantities of plastic waste. © 2015 Elsevier Ltd.

Vizel M.,Tel Aviv University | Loya Y.,Tel Aviv University | Downs C.A.,Haereticus Environmental Laboratory | Kramarsky-Winter E.,Tel Aviv University
Marine Biotechnology | Year: 2011

We describe here a method for the micropropagation of coral that creates progeny from tissue explants derived from a single polyp or colonial corals. Coral tissue explants of various sizes (0.5-2.5 mm in diameter) were manually microdissected from the solitary coral Fungia granulosa. Explants could be maintained in an undeveloped state or induced to develop into polyps by manipulating environmental parameters such as light and temperature regimes, as well as substrate type. Fully developed polyps were able to be maintained for a long-term in a closed sea water system. Further, we demonstrate that mature explants are also amenable to this technique with the micropropagation of second-generation explants and their development into mature polyps. We thereby experimentally have established coral clonal lines that maintain their ability to differentiate without the need for chemical induction or genetic manipulation. The versatility of this method is also demonstrated through its application to two other coral species, the colonial corals Oculina patigonica and Favia favus. © 2010 Springer Science+Business Media, LLC.

Vijayavel K.,University of Hawaii at Manoa | Downs C.A.,Haereticus Environmental Laboratory | Ostrander G.K.,University of Hawaii at Manoa | Richmond R.H.,University of Hawaii at Manoa
Comparative Biochemistry and Physiology - C Toxicology and Pharmacology | Year: 2012

Biochemical and molecular biomarkers tools are utilized as early warning signatures of contaminant exposure to target and non-target organisms. The objective of this study was to investigate the sublethal effects of iron chloride to the larvae of the lace coral Pocillopora damicornis by measuring a suit of oxidative-stress biomarkers. The larvae were exposed to a range of sublethal concentrations of iron chloride (0.01, 0.1, 1, 10, and 100 ppm) for seven days. With reference to oxidative stress biomarkers, the no-observed effect concentration (NOEC) and the lowest observed effect concentration (LOEC) of iron chloride were observed to be 0.01 and 100 ppm respectively. At the end of the seventh day the antioxidant status of the larvae was evaluated by the levels of glutathione (GSH), glutathione peroxidase (GPX), glutathione reductase (GR), and glutathione-S-transferase (GST), in both experimental and control groups. For the quantification of cellular oxidative damage, lipid peroxidation (LPO) activity was determined in the same and the extent of DNA damage was assessed by the expression of DNA apurinic/apyrimidinic (AP) sites. Iron chloride exhibited a concentration-dependent inhibition of GSH and GPX and induction of GR, GST, LPO, and DNA-AP sites in the P. damicornis larvae when compared to the control group. The oxidative stress biomarkers of the larvae exposed to 0.1, 1, and 10 ppm of iron chloride did not show any significant overall differences when compared to the control group. However the activities of LPO, GSH, GPX, GR, GST and DNA-AP in the larval group exposed to 100 ppm of iron chloride exhibited statistically significant (P = 0.002, 0.003, 0.002, 0.002, 0.005 and 0.007) differences when compared to the control group. The research results indicated that iron chloride in concentrations at the 100 ppm level caused oxidative stress in the P. damicornis larvae. © 2011 Elsevier Inc. All rights reserved.

Downs C.A.,Haereticus Environmental Laboratory | Ostrander G.K.,University of Hawaii at Manoa | Rougee L.,University of Hawaii at Manoa | Rongo T.,University of Guam | And 5 more authors.
Ecotoxicology | Year: 2012

Coral reefs throughout the world are exhibiting documented declines in coral cover and species diversity, which have been linked to anthropogenic stressors including land-based sources of pollution. Reductions in coastal water and substratum quality are affecting coral survivorship, reproduction and recruitment, and hence, the persistence of coral reefs. One major obstacle in effectively addressing these declines is the lack of tools that can identify cause-and-effect relationships between stressors and specific coral reef losses, while a second problem is the inability to measure the efficacy of mitigation efforts in a timely fashion. We examined corals from six coral reefs on Guam, Mariana Islands, which were being affected by different environmental stressors (e.g. PAH's, pesticides, PCB's and sedimentation). Cellular diagnostic analysis differentiated the cellular-physiological condition of these corals. Examination of protein expression provided insight into their homeostatic responses to chemical and physical stressors in exposed corals prior to outright ortality, providing improved opportunities for developing locallybased management responses. This approach adds critically needed tools for addressing the effects of multiple stressors on corals and will allow researchers to move beyond present assessment and monitoring techniques that simply document the loss of coral abundance and diversity. © 2011 Springer Science+Business Media, LLC.

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