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Ion channel missense mutations cause disorders of excitability by changing channel biophysical properties. As an increasing number of new naturally occurring mutations have been identified, and the number of other mutations produced by molecular approaches such as in situ mutagenesis has increased, the need for functional analysis by patch-clamp has become rate limiting. Here we compare a patch-clamp robot using planar-chip technology with human patch-clamp in a functional assessment of a previously undescribed Nav1.7 sodium channel mutation, S211P, which causes erythromelalgia. This robotic patch-clamp device can increase throughput (the number of cells analysed per day) by 3- to 10-fold. Both modes of analysis show that the mutation hyperpolarizes activation voltage dependence (8 mV by manual profiling, 11 mV by robotic profiling), alters steady-state fast inactivation so that it requires an additional Boltzmann function for a second fraction of total current (approximately 20% manual, approximately 40% robotic), and enhances slow inactivation (hyperpolarizing shift--15 mV by human,--13 mV robotic). Manual patch-clamping demonstrated slower deactivation and enhanced (approximately 2-fold) ramp response for the mutant channel while robotic recording did not, possibly due to increased temperature and reduced signal-to-noise ratio on the robotic platform. If robotic profiling is used to screen ion channel mutations, we recommend that each measurement or protocol be validated by initial comparison to manual recording. With this caveat, we suggest that, if results are interpreted cautiously, robotic patch-clamp can be used with supervision and subsequent confirmation from human physiologists to facilitate the initial profiling of a variety of electrophysiological parameters of ion channel mutations.

The Food Safety Authority of Ireland in collaboration with the Marine Institute and An Board Iascaigh Mhara (Sea Fisheries Board) has carried out a surveillance study of levels of dioxins (PCDDs), furans (PCDFs) polychlorinated biphenyls (PCBs), and brominated flame retardants (BFRs), specifically polybrominated diphenylethers (PBDEs) and hexabromocyclododecane (HBCD), in a variety of fish species and fishery products, including fresh and processed products available on the Irish market. The study was undertaken because of concern about the possible effects on human health of these bio-persistent environmental contaminants, known to be present in a number of foodstuffs, notably meat, fish, eggs and dairy products. The study showed that levels of PCDDs and PCDFs in Irish fish and fishery products available on the Irish market were well below existing EC legal limits for these contaminants as laid down in Regulation 466/2001. The lowest level was found in a sample of canned tuna (0.012 ng WHO TEQ/kg whole weight) with the highest level found in a farmed salmon sample (0.82 ng WHO TEQ/kg whole weight), compared with the maximum level under the legislation of 4 ng WHO TEQ/kg whole weight. The levels found were also below the new limits for dioxin-like PCBs (dl-PCBs) and for the sum of WHO-TEQs for PCDDs, PCDFs and dioxin-like PCBs, which were introduced in November, 2006 via Regulation 199/2006. The upper-bound mean levels of PCDDs, PCDFs and dioxin-like PCBs expressed as total WHOTEQs ranged from 0.05 – 2.15 ng/kg WHO TEQ whole weight, which can be compared with the new maximum level of 8 ng WHO TEQ/kg whole weight for the sum of PCDDs, PCDFs and dioxin-like PCBs. Results of this study are in line with those from previous FSAI studies on PCDD and PCDF levels in fish and also in meat, milk and eggs, and indicate relatively low levels of these contaminants in fishery produce available in the Irish marketplace. Reductions of PCDD/Fs and dl-PCBs in Irish farmed salmon were observed in comparison to levels measured in a previous FSAI/MI survey in 2001, in which a mean level of 4.02 ng WHO TEQ/kg whole weight was detected compared with 2.15 ng/kg WHO TEQ whole weight in the present study. Similar observations can be made for levels reported in a study carried out by An Board Iascaigh Mhara in 2004, in which a mean level of 1.75 ng WHO TEQ/kg whole weight was reported. Concentrations of brominated flame retardants were also low. The mean PBDE concentrations ranged from, Funder: Marine Institute

In accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs, water samples from major shellfish growing areas were tested for physicochemical parameters and shellfish were tested for trace metal levels. In 2003, a total of 30 samples were analysed for trace metals. All mercury concentrations measured were below or close to the limit of quantification, 0.03 mg/kg wet weight, which is well within the European maximum level of 0.50 mg/kg wet weight for mercury in bivalve molluscs. Levels of lead were typically low, with a mean of 0.26 mg/kg wet weight and maxima of 1.04 mg/kg wet weight, also below the respective European maximum level of 1.50 mg/kg wet weight. In addition, levels of cadmium were all below the European maximum level of 1 mg/kg wet weight, though the level of cadmium determined at Castlegregory in Tralee Bay was 0.97 mg/kg, close to the European limit. Castlegregory has not been included in the sampling programme since 1994, but will be included in future monitoring. There are no internationally agreed standards or guidelines available for the remaining trace metals in shellfish. A compilation by the OSPAR Commission of standard and guidance values applied by member states of OSPAR indicated the Spanish standard for copper in shellfish of 20 mg/kg wet weight to be the strictest available. This excludes oysters for which a higher standard of 60 mg/kg wet weight has been set, as oysters accumulate copper to higher levels. All copper results were within these Spanish standards. The results obtained provide evidence of the clean, unpolluted nature of Irish shellfish and shellfish producing waters. As in previous years, the water quality from shellfish growing areas was good and conformed to the requirements of the Directive. Petroleum hydrocarbons were not visible in any of the shellfish waters or as deposits on the shellfish. This survey confirms previous studies (Glynn et al., 2004, 2003a, 2003b; McGovern et al., 2001; Bloxham et al., 1998; Smyth et al., 1997 and Nixon et al., 1995, 1994, and 1991), which show that contamination from trace metals is low in Irish shellfish aquaculture., Funder: Marine Institute

The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2003, a total of 45 samples from 22 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible tissue. The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.60 mg/kg wet weight with a mean and median of 0.08 and 0.06 mg/kg respectively. The maximum level was found in a dogfish sample (species tentatively identified as Lesser Spotted Dogfish) from Howth. It is most likely that the fish from which this sample was taken were destined for whelk bait and as such there are no human health implications. The remainder of the mercury levels were within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EU (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafoods are effectively free from mercury contamination. A total of 20 samples were analysed for lead and cadmium. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively set by the EU. Randomly selected samples were also analysed for other trace metals. There are no internationally agreed standards or guidelines available for the remaining trace metals in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting countries to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed., Funder: Marine Institute

Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water and trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2002, a total of 24 samples from 22 different shellfish sites were analysed for chlorinated hydrocarbons and trace metals, including nickel and silver. The median concentration of mercury in shellfish sampled in 2002 was, Funder: Marine Institute

The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2002, a total of 38 samples from 20 different species of finfish were collected from five major Irish fishing ports and analysed for total mercury concentration in the edible tissue (Common names and species names are listed in Appendix 3). The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.46 mg/kg wet weight with a mean and median of 0.09 and 0.06 mg/kg respectively. These levels are within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EU (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively, set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standards or guidance values for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed., Funder: Marine Institute

Major shellfish growing areas were sampled in accordance with the monitoring requirements of Council Directive 79/923/EEC, on the quality required of shellfish waters, and Council Directive 91/492/EEC, laying down the health conditions for the production and placing on the market of live bivalve molluscs. Data for physicochemical parameters in water, trace metal levels and chlorinated hydrocarbon concentrations in shellfish are presented. In 2001, a total of 23 samples from 20 different shellfish sites were analysed for trace metals and chlorinated hydrocarbons. The median concentration of mercury in shellfish sampled in 2001 was, Funder: Marine Institute

The Marine Institute sample a range of finfish species landed at major Irish ports on an annual basis, in accordance with the monitoring requirements of various European legislation designed to ensure food safety. During 2001, a total of 44 samples from 20 different species of finfish were collected from six major Irish fishing ports and analysed for total mercury concentration in the edible tissue. The concentration of mercury ranged from less than the limit of quantitation (0.03 mg/kg wet weight) to 0.42 mg/kg wet weight with a mean and median of 0.09 and 0.07 mg/kg respectively. These levels are within the maximum limit of 0.50 mg/kg wet weight for mercury in fishery products set by the EC (1 mg/kg for selected species). This survey confirms previous studies, which show that Irish seafood is effectively free from mercury contamination. Selected samples were also analysed for other trace metals and chlorinated hydrocarbons. Overall, the levels of lead and cadmium detected in the edible portion of the fish were low and well within the standard values of 0.20 and 0.05 mg/kg wet weight respectively, set by the EU. There are no internationally agreed standards or guidelines available for the remaining trace metals and chlorinated hydrocarbons in fishery products. Therefore results are compared with the strictest standard or guidance value for fish tissue, which are applied by contracting parties to the OSPAR Convention. The levels of these additional contaminants are well below the strictest values listed., Funder: Marine Institute