Innovation in regulatory approaches for endocrine disrupting chemicals: The journey to risk assessment modernization in Canada

Globally, regulatory authorities grapple with the challenge of assessing the hazards and risks to human and ecosystem health that may result from exposure to chemicals that disrupt the normal functioning of endocrine systems. Rapidly increasing number of chemicals in commerce, coupled with the reliance on traditional, costly animal experiments for hazard characterization - often with limited sensitivity to many important mechanisms of endocrine disruption -, presents ongoing challenges for chemical regulation. The consequence is a limited number of chemicals for which there is sufficient data to assess if there is endocrine toxicity and hence few chemicals with thorough hazard characterization. To address this challenge, regulatory assessment of endocrine disrupting chemicals (EDCs) is benefiting from a revolution in toxicology that focuses on New Approach Methodologies (NAMs) to more rapidly identify, prioritize, and assess the potential risks from exposure to chemicals using novel, more efficient, and more mechanistically driven methodologies and tools. Incorporated into Integrated Approaches to Testing and Assessment (IATA) and guided by conceptual frameworks such as Adverse Outcome Pathways (AOPs), emerging approaches focus initially on molecular interactions between the test chemical and potentially vulnerable biological systems instead of the need for animal toxicity data. These new toxicity testing methods can be complemented with in silico and computational toxicology approaches, including those that predict chemical kinetics. Coupled with exposure data, these will inform risk-based decision-making approaches. Canada is part of a global network collaborating on building confidence in the use of NAMs for regulatory assessment of EDCs. Herein, we review the current approaches to EDC regulation globally (mainly from the perspective of human health), and provide a perspective on how the advances for regulatory testing and assessment can be applied and discuss the promises and challenges faced in adopting these novel approaches to minimize risks due to EDC exposure in Canada, and our world.

Forage fish and polycyclic aromatic compounds in the Fort McMurray oil sands area: Body burden comparisons with environmental distributions and consumption guidelines

The Fort McMurray region in northeastern Alberta (Canada) is rich in natural sources of polycyclic aromatic compounds (PACs) from exposed bitumen beds; anthropogenic sources are being released with increased oil sands industry expansion. Here we report on investigations of PACs (47 compounds) in three species of forage fish collected during the 2012-2013 Joint Oil Sands Monitoring Program (JOSMP) fish health investigations and compare results with PAC data for sediment and water collected under JOSMP and earlier programs. PAC concentrations in sediments varied three orders in magnitude and were highest at downstream tributary mouths, which flowed through the exposed McMurray Formation, and along reaches of the Athabasca River where the formation was exposed. PAC concentrations in water were less variable but with higher concentrations near exposed bitumen beds. Forage fish exhibited the weakest spatial gradients in ΣPACs concentration, which averaged 102 ± 32 ng/g in trout-perch from the Athabasca River, 125 ± 22 ng/g in lake chub from the Ells River, and 278 ± 267 ng/g in slimy sculpin from the Steepbank, Firebag, and Dunkirk Rivers. Low-molecular weight compounds, particularly naphthalenes and fluorenes, dominated fish PACs. Phenanthrenes occurred in greater percent composition in fish caught in areas where PAC concentrations in sediments were higher due to the proximity of bitumen sources than in other areas. Dibenzothiophene, a major component of bitumen PAC, was a minor component of fish ΣPACs. Forage fish PAC concentrations were below fish consumption guidelines established by the European Commission (2011) and for the reopening of the commercial fisheries closed by the Deepwater Horizon oil spill. PAC concentrations in forage fish were similar to concentrations observed in many other studies (fish market surveys, estuaries, and marine waters) and lower than in fish sampled from highly impacted areas (near refineries, harbors, and other industrialized areas).

Patient access to Psychiatric Records: The Patients’ View

The passing of legislation relating to subject access to personal health data has been accompanied by concern about the possible harmful effects of this development on patients. Despite the lack of substantive evidence psychiatric patients have been regarded as the group most at risk. This study investigates the subjective views of patients on access to records on two psychiatric wards.

Impact of activated sludge configuration and operating conditions on in vitro and in vivo responses and trace organic compound removal

This study tested municipal sewage effluents generated at the pilot scale using conventional activated sludge (CAS), nitrifying activated sludge (CAS-N) and biological nutrient removal (BNR) in terms of the removal of trace organic compounds (TrOCs) and final effluent quality as indicated by yeast estrogenicity screening (YES), short term zebrafish reproduction and fathead minnow life-cycle tests. Under cold weather conditions (extended SRTs), the BNR configuration reduced the concentrations of the largest number of TrOCs while under warm weather conditions (reduced SRTs) the CAS-N was most effective. By comparison, YES test results indicated statistically lower responses in the BNR effluent in the warm weather tests and no difference between the effluents of CAS-N and BNR in the cold weather tests. Short term tests with adult zebrafish revealed no impact of the BNR and CAS-N effluents on egg production. By contrast egg production and gene expression in the CAS-exposed zebrafish were substantially less than that of control exposures and were similar to that of exposures to ammonia at similar concentrations as the CAS exposures. In fathead minnow life-cycle tests, exposures to CAS effluent (70-50% v/v) resulted in considerable mortality, reduced growth and reduced egg production that was likely due to the elevated ammonia concentrations. The CAS-N effluent (100% v/v) also resulted in some mortality and reduced growth and egg production in the fathead minnows. By contrast, the BNR effluent (100% v/v) had no effect on mortality, growth or egg production. The results suggest that enhancements to wastewater treatment plants that are associated with improved nitrogen removal can result in enhanced removal of TrOCs and can reduce the harmful effects of the effluents on aquatic biota.

Differential changes in gene expression in rainbow trout hepatocytes exposed to extracts of oil sands process-affected water and the Athabasca River

The oil sands region of northern Alberta represents the world's largest reserves of bitumen, and the accelerated pace of industrial extraction activity has raised concern about the possible impacts on the Athabasca River and its tributaries. An ecotoxicogenomic study was undertaken on Oncorhynchus mykiss trout hepatocytes exposed to extracts of water samples near the oil sand development area, as well as to oil sands process-affected water (OSPW) extracts using the quantitative reverse transcriptase polymerase chain reaction technique. The expression of the following genes (mRNA) was monitored to track changes in xenobiotic biotransformation (CYP1A1, CYP3A4, glutathione S-transferase, multi-drug resistance transporter), estrogenicity (estrogen receptor and vitellogenin), oxidative stress (superoxide dismutase and metallothionein) and DNA repair activity (DNA ligase). The extent of DNA-aromatic hydrocarbon adducts was also determined in cells by immuno-staining. A comparative analysis of gene expression between the river/lake and OSPW samples revealed that CYP3A4, metallothioneins, DNA ligase and GST genes, were specifically expressed by OSPW. Cells exposed to OSPW, commercial naphthenic acids, and benzo(a)pyrene showed increased polyaromatic hydrocarbon DNA-adducts, as determined by cell immunofluorescence analysis. Other genes were induced by all types of water samples, although the induction potential was stronger in OSPW most of the time (e.g., VTG gene was expressed nearly 15-fold by surface waters from the lake and river samples but increased to a maximum of 31-fold in OSPW). A multivariate discriminant function analysis revealed that the lake and river water samples were well discriminated from the OSPW. The CYP3A4 gene was the most highly expressed gene in cells exposed to OSPW and responded less to the lake or river water in the Athabasca River area. This study identified a suite of gene targets that responded specifically to OSPW extracts, which could serve as toxicogenomic fingerprints of OSPW contamination.

Preliminary fingerprinting of Athabasca oil sands polar organics in environmental samples using electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry

There is a growing need to develop analytical methods that can distinguish compounds found within industrially derived oil sands process water (OSPW) from those derived from natural weathering of oil sands deposits. This is a difficult challenge as possible leakage beyond tailings pond containments will probably be in the form of mixtures of water-soluble organics that may be similar to those leaching naturally into aquatic environments. We have evaluated the potential of negative ion electrospray ionization high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICRMS) for comparing oil sands polar organics from tailing ponds, interceptor wells, groundwater, river and lake surface waters. Principal component analysis was performed for all species observed. which included the O(2) class (often assumed to be monocarbxoylic naphthenic acids) along with a wide range of other species including humic substances in the river and lake samples: O(n) where n=1-16; NO(n) and N(2)O(n) where n=1-13; and O(n)S and O(n)S(2) where n=1-10 and 1-8, respectively. A broad range of species was investigated because classical naphthenic acids can be a small fraction of the 'organics' detected in the polar fraction of OSPW, river water and groundwater. Aquatic toxicity and environmental chemistry are attributed to the total organics (not only the classical naphthenic acids). The distributions of the oil sands polar organics, particularly the sulfur-containing species, O(n)S and O(n)S(2), may have potential for distinguishing sources of OSPW. The ratios of species containing O(n) along with nitrogen-containing species: NO(n), and N(2)O(n), were useful for differentiating organic components derived from OSPW from those found in river and lake waters. Further application of the FTICRMS technique for a diverse range of OSPW of varying ages and composition, as well as the surrounding groundwater wells, may be critical in assessing whether leakage from industrial sources to natural waters is occurring.

Hip surveillance in children with cerebral palsy

We studied prospectively the impact of a hip surveillance clinic on the management of spastic hip disease in children with cerebral palsy in a tertiary referral centre. Using a combination of primary clinical and secondary radiological screening we were able to detect spastic hip disease at an early stage in most children and to offer early surgical intervention. The principal effect on surgical practice was that more preventive surgery was carried out at a younger age and at a more appropriate stage of the disease. The need for reconstructive surgery has decreased and that for salvage surgery has been eliminated. Displacement of the hip in children with cerebral palsy meets specific criteria for a screening programme. We recommend that hip surveillance should become part of the routine management of children with cerebral palsy. The hips should be examined radiologically at 18 months of age in all children with bilateral cerebral palsy and at six- to 12-monthly intervals thereafter. A co-ordinated approach by orthopaedic surgeons and physiotherapists may be the key to successful implementation of this screening programme.

Hip surveillance in children with cerebral palsy. Impact on the surgical management of spastic hip disease

We studied prospectively the impact of a hip surveillance clinic on the management of spastic hip disease in children with cerebral palsy in a tertiary referral centre. Using a combination of primary clinical and secondary radiological screening we were able to detect spastic hip disease at an early stage in most children and to offer early surgical intervention. The principal effect on surgical practice was that more preventive surgery was carried out at a younger age and at a more appropriate stage of the disease. The need for reconstructive surgery has decreased and that for salvage surgery has been eliminated. Displacement of the hip in children with cerebral palsy meets specific criteria for a screening programme. We recommend that hip surveillance should become part of the routine management of children with cerebral palsy. The hips should be examined radiologically at 18 months of age in all children with bilateral cerebral palsy and at six- to 12-monthly intervals thereafter. A co-ordinated approach by orthopaedic surgeons and physiotherapists may be the key to successful implementation of this screening programme.

The effect of botulinum toxin type A and a variable hip abduction orthosis on gross motor function: a randomized controlled trial

Hip displacement is the second most common deformity after equinus in children with cerebral palsy (CP), and may result in dislocation, pain, fixed deformity and loss of function. We studied the combined effects of intramuscular injections of botulinum toxin type A (BTX-A) to the adductors and hamstrings and a variable hip abduction orthosis (SWASH), on gross motor function, hip displacement and progression to surgery, in a randomized clinical trial. Thirty-nine children, with bilateral spastic cerebral palsy, and mean age 3 years + 2 months (range 1 year+7 months--4 years +10 months) entered the trial. Gross Motor Function Classification System (GMFCS) levels were as follows: one child was level II, 11 were level III, 13 were level IV and 14 were level V. After concealed randomization, 20 were allocated to the control group and 19 to the intervention group. Thirty-five children completed the follow up at 1 year. The novel intervention group received up to 4.0 U BOTOX/kg/muscle, 16 U/kg/body weight every 6 months plus the use of a SWASH brace. The control group received clinical best practice comprising physiotherapy but no hip abduction bracing. Both groups showed improvements in total Gross Motor Function Measure (GMFM) score [mean 6.0% BTX-A group; 6.1% Control; 95% CI -- 6.7, 6.5 (NS)], however, there was no additional treatment effect for the study group. There were similar improvements on GMFM goal scores and GMFM-66 scores, but again no additional treatment effect was observed. Multiple regression of change in total GMFM by GMFCS classification for each group showed greater improvement in the total scores from baseline in the BTX-A/SWASH treated group than the control group. In the first year, nine children (two in the intervention group and seven in the control group) required soft tissue surgery because of progressive hip migration in excess of 40%. A longer-term follow up of a larger cohort may be required to determine the effect of the combined treatment on hip displacement.

African-Caribbean men remanded to Brixton Prison. Psychiatric and forensic characteristics and outcome of final court appearance

BACKGROUND

African-Caribbean men are over-represented in psychiatric and forensic services and in the prison population. A failure of community services to engage mentally ill African-Caribbean men and their presentation through the criminal justice system culminates in a repeated pattern of forensic service and criminal justice system contact.

METHOD

We carried out a cross-sectional survey during a one-year period of a sample of potentially mentally ill men remanded to HMP Brixton in south London. Men were interviewed to establish their place of birth, first language, socio-demographic profile, ethnicity, psychiatric diagnosis, levels of alcohol and substance misuse, criminality, violence involved in their index offence, past psychiatric and forensic contacts and outcome of court appearance.

RESULTS

Two hundred and seventy-seven men were interviewed. In comparison with White men, African-Caribbean men were more often diagnosed as having schizophrenia and were more often sent to hospital under a mental health act order. African-Caribbean men were remanded in custody despite more stable housing conditions and more favourable indices of lifetime criminality, substance misuse and violence.

CONCLUSIONS

Community services, including diversion schemes, should be especially sensitive to African-Caribbean men with schizophrenia who 'fall out of care', who are not diverted back into care and are therefore unnecessarily remanded.

The Belmarsh Scheme. A prospective study of the transfer of mentally disordered remand prisoners from prison to psychiatric units

BACKGROUND

Contracting in psychiatric services from the NHS into prisons has been advocated to improve the care of the mentally disordered in custody. The Belmarsh Scheme is such a service.

METHOD

A prospective study investigating the characteristics of a six-month cohort of remand prisoners requiring transfer to hospital and evaluating the service's effectiveness.

RESULTS

Fifty-three (4.3%; 95% CL 3.2% to 5.6%) of the 1229 new remands required transfer to hospital; all were accepted. The transfer group contained a higher proportion of black men (51%) than all other remands (30%) (difference 21%; 95% CL 8% to 35%, P = 0.002). Transfer times were lower than those reported for a neighbouring prison.

CONCLUSIONS

The Belmarsh Scheme secured in-patient psychiatric care rapidly for all those identified as needing it.

A reduced-rank multivariate regression approach to aquatic joint toxicity experiments

Classical multivariate regression techniques can lead to an asymptotically efficient restricted estimator of the regression matrix if there is evidence that the regression matrix is of reduced rank. A sublethal joint toxicity experiment involving two agents is used to illustrate this approach.

Suppression of renin production in patients undergoing coronary artery bypass

Twenty patients undergoing elective myocardial revascularization for coronary insufficiency were divided into two equal groups. In 10 patients, propranolol was discontinued 24 hours before operation while the remaining patients received propranolol until the day of operation. Plasma renin was elevated in the intensive care unit in the control group (p < 0.05) whereas patients receiving propranolol did not demonstrate significant elevation of plasma renin. Systemic vascular resistance was elevated in both groups in the intensive care unit (p < 0.05) and was associated with hypertension as defined by a blood pressure of greater than or equal to 160/100 mm Hg in 80% of the control patients and 70% of patients receiving propranolol. We conclude from this study that renin metabolism does not contribute significantly to the production of hypertension following coronary artery operation.