Probabilistic risk assessment of the environmental impacts of pesticides in the Crocodile (west) Marico catchment, North-West Province

External agricultural inputs, such as pesticides, may pose risks to aquatic ecosystems and affect aquatic populations, communities and ecosystems. To predict these risks, a tiered approach was followed, incorporating both the PRIMET and PERPEST models. The first-tier PRIMET model is designed to yield a relatively worst-case risk assessment requiring a minimum of input data, after which the effects of the risks can be refined using a higher tier PERPEST model. The risk assessment initially depends on data supplied from local landowners, pesticide characteristic, application scheme and physical scenario of the environment under question. Preliminary results are presented, together with ecotoxicological data on several frequently-used pesticides in a section of the Crocodile (west) Marico Water Management Area (WMA) in South Africa. This area is historically known to have a high pesticide usage, with deltamethrin, aldicarb, parathion, cypermethrin and dichlorvos being the main pesticides used. Deltamethrin was indicated as having the highest probability of risks to aquatic organisms occurring in the study area. Cypermethrin, parathion, dichlorvos, carbaryl, romoxynil, linuron, methomyl and aldicarb were all indicated as having possible risks (ETR 1-100) to the aquatic environment. Pesticides posing no risk included fenamiphos, abamectin, pendimethalin, captan, endosulfan, alachlor, bentazone and cyromazine (ET

Probabilistic risk assessment of the environmental impacts of pesticides in the Crocodile (west) Marico catchment, North-West Province

External agricultural inputs, such as pesticides, may pose risks to aquatic ecosystems and affect aquatic populations, communities and ecosystems. To predict these risks, a tiered approach was followed, incorporating both the PRIMET and PERPEST models. The first-tier PRIMET model is designed to yield a relatively worst-case risk assessment requiring a minimum of input data, after which the effects of the risks can be refined using a higher tier PERPEST model. The risk assessment initially depends on data supplied from local landowners, pesticide characteristic, application scheme and physical scenario of the environment under question. Preliminary results are presented, together with ecotoxicological data on several frequently-used pesticides in a section of the Crocodile (west) Marico Water Management Area (WMA) in South Africa. This area is historically known to have a high pesticide usage, with deltamethrin, aldicarb, parathion, cypermethrin and dichlorvos being the main pesticides used. Deltamethrin was indicated as having the highest probability of risks to aquatic organisms occurring in the study area. Cypermethrin, parathion, dichlorvos, carbaryl, bromoxynil, linuron, methomyl and aldicarb were all indicated as having possible risks (ETR 1-100) to the aquatic environment. Pesticides posing no risk included fenamiphos, abamectin, pendimethalin, captan, endosulfan, alachlor, bentazone and cyromazine (ETR<1). The pesticides posing a possible risk to the aquatic ecosystem were evaluated further to determine their effects on 8 grouped endpoints using the PERPEST effect model. Deltamethrin and cypermethrin were again noted as posing the greatest risk and clear effects were eminent for aquatic insects and macro-crustaceans, followed by micro-crustaceans and rotifers. High percentages of clear effects on insects were also observed for carbaryl, parathion and dichlorvos. Linuron was indicated as having minimal clear effects on community metabolism, macrophytes and phytoplankton classes, while lesser clear effects of bromoxynil occurred on periphyton communities. Application of both the lower-tier PRIMET and higher-tier PERPEST models showed similar trends in that they both ranked the top 5 pesticides in the same order of risk. This approach offers a significant improvement over the presently-used simulation models or use of safety factors. It is therefore especially useful in developing countries such as South Africa, where pesticide environmental risk information is scarce. Although these models were effectively used in this study, it still has to be validated further under South African conditionsKeywords: risk-assessment model, pesticides, aquatic ecosyste

Best practice model for outpatient psychiatric pharmacy practice, part 2: Confirmation of the attribute statements

Introduction: The American Association of Psychiatric Pharmacists (AAPP) used multiple modalities to develop and refine 28 attribute statements to describe a best practice model for outpatient psychiatric pharmacists. Before addressing implementation, assessment, and field testing, it was necessary to finalize and confirm the statements and their supporting narratives among stakeholders. The objective of this project was to confirm the attribute statements and supporting justifications for a best practice model for outpatient psychiatric pharmacists providing direct patient care. Methods: The 4 phases that resulted in the 28 attribute statements and supporting narratives have been described and published elsewhere. As part of phase 5, the confirmation survey was distributed to pharmacists and resident members of AAPP in November 2021 for 3 weeks. Results: The survey respondents (n = 74; 6.1%) were licensed pharmacists for an average of 15.6 years (SD = 12.0) and had been practicing as psychiatric pharmacists for an average of 11.3 years (SD = 10.4). Slightly more than half (54.2%) of the respondents reported practicing in the outpatient setting and three-fourths (74.3%) were Board Certified Psychiatric Pharmacists. For each of the 28 statements, more than 90% of respondents either agreed or agreed with minimal reservations. Discussion: Given the high degree of agreement on the proposed practice model statements, they will be used as the basis for the outpatient psychiatric pharmacist best practice model. Next steps in developing this model include establishing implementation guidance, determining appropriate metrics for evaluation of these statements in practice, and establishing appropriate field-testing methods

Best practice model for outpatient psychiatric pharmacy practice, part 1: Development of initial attribute statements

Introduction: A 2019 survey identified significant variability of practice characteristics among outpatient psychiatric pharmacists (OPPs). No published model establishes which attributes constitute best practice for OPPs. By developing a consensus for best practice model attributes, OPPs can work toward consistent, effective patient care. This project aimed to develop attribute statements for a best practice model for OPPs providing direct patient care. Methods: Board Certified Psychiatric Pharmacists and American Association of Psychiatric Pharmacists (AAPP) members were questioned using a 5-phase (P1-P5) survey and summit approach. The phases were: P1, broad ideation survey; P2, 10-person summit to develop draft statements; P3, survey of the draft statements for acceptance; P4, summit to resolve review feedback; and P5, survey of AAPP membership to confirm the finalized statements. Results: P1 survey results generated a list of 143 possible attributes that informed the P2 summit, which were refined to 28 statements. P3 survey results confirmed at least 70% agreement with each statement. The P4 summit evaluated all P3 survey results and made significant modifications to 4 statements. Informal feedback was sought with other stakeholders, and supporting narratives and references were developed to provide clarity regarding the intent of each statement. Finalized statements and supporting narratives were confirmed in the P5 survey. Discussion: The 28 attribute statements were developed over 18 months by gathering input and consensus through multiple modalities, including 3 surveys, 2 summit meetings, and numerous informal feedback requests. The agreement on the attribute statements was consistently high across all phases. The final attribute statements are presented elsewhere in this issue

Natural archives of long-range transported contamination at the remote lake Letšeng-la Letsie, Maloti Mountains, Lesotho

Naturally accumulating archives, such as lake sediments and wetland peats, in remote areas may be used to identify the scale and rates of atmospherically deposited pollutant inputs to natural ecosystems. Co-located lake sediment and wetland cores were collected from Letšeng-la Letsie, a remote lake in the Maloti Mountains of southern Lesotho. The cores were radiometrically dated and analysed for a suite of contaminants including trace metals and metalloids (Hg, Pb, Cu, Ni, Zn, As), fly-ash particles, stable nitrogen isotopes, polycyclic aromatic hydrocarbons (PAHs) and persistent organic pollutants such as polychlorinated biphenyls (PCBs), polybrominated flame retardants (PBDEs) and hexachlorobenzene (HCB). While most trace metals showed no recent enrichment, mercury, fly-ash particles, high molecular weight PAHs and total PCBs showed low but increasing levels of contamination since c.1970, likely the result of long-range transport from coal combustion and other industrial sources in the Highveld region of South Africa. However, back-trajectory analysis revealed that atmospheric transport from this region to southern Lesotho is infrequent and the scale of contamination is low. To our knowledge, these data represent the first palaeolimnological records and the first trace contaminant data for Lesotho, and one of the first multi-pollutant historical records for southern Africa. They therefore provide a baseline for future regional assessments in the context of continued coal combustion in South Africa through to the mid-21st century

An ecological risk assessment of pesticides using a probabilistic model and its implementation on the Crocodile and Magalies Rivers, South Africa

D.Phil.South Africa is the highest produce-producing and therefore the highest pesticide consumer on the African continent. Although greatly beneficial to the industry, indiscriminate and over usage of these agrochemicals pose a risk to the aquatic ecosystems through non-point source pollution. Data on these risks are limited in the developing countries such as Africa since limited environmental monitoring of pesticides is undertaken. This is due to technical, logistical and economical constraints in determining the links between exposure and effect on non-target organisms. Methods that are able to screen for and monitor pesticides that could pose a risk according to site-specific scenarios are therefore necessary. Economical and easy-to-use predictive models incorporated into Preliminary Risk Assessments (PRA’s) are useful in this regard and have been developed and applied globally to assist in estimating the probability of risks of pesticides associated with aquatic ecosystems. Currently no such risk assessment model is applied in South Africa for this purpose. The main aim of the present study was to present and assess the suitability of selected PRA models as preliminary screening tools for estimating potential pesticide exposure and associated effects within aquatic ecosystems. To achieve this, the primary objectives were to apply and validate these models for assessing predicted risks and to relate these to actual ecological hazards by monitoring the exposure and effects of selected pesticides that were identified as potentially posing a risk. It was hypothesised that the data determined by these models would elucidate the association between potential risks of pesticides and actual environmental impacts and could therefore be applied and validated for South African conditions. A framework was thus developed using multidisciplinary approaches to predict the risks of agricultural pesticides to non-target aquatic organisms and to validate these risks in an area known to have a high pesticide usage, namely the Crocodile (west) Marico catchment. This area is representative of a typical farming community in the subtropical central area of South Africa. It is a catchment area that exhibits high urban and agricultural usage, which has compromised the overall ecological integrity of the aquatic systems. The focus of the study was on the Crocodile (west) and Magalies Rivers and the associated irrigation canal network systems. The present study was based on integrating multidisciplinary techniques following the implementation of a tiered approach for assessing the ecological risks of selected pesticides known to be used within the Crocodile (west) Marico catchment. Tier 1 starts with the PRA SUMMARY xx assuming a relatively worst-case scenario by identifying pesticides most commonly used (through surveys) and estimating exposures posing a potential risk to the aquatic environment using the PRIMET (Pesticide Risks In the tropics to Man, Environment and Trade) model. The second tier can establish a more realistic characterisation of risk for the pesticide application scenarios of interest by using models such as PERPEST (Predicting the Ecological Risks of PESTicides), PEARL (Pesticide Emission Assessment of Regional and Local Scales), TOXSWA (TOXic substances in Surface Waters), or SSDs (Species Sensitivity Distributions). Higher tiers then include comparing the results from the PRA model predictions to the actual hazards of pesticides and can determine if these risk models are valid under South Africa conditions. This can be achieved using a combination of laboratory- and field-based monitoring assessments in the form of a triad approach (using chemical, toxicological and ecological assessments) to construct several lines-of-evidence (LoEs). The risk assessment process ends with a summary and integration of the data based on the multiple LoEs gathered during monitoring using a weight-of-evidence (WoE) approach

The use of feathers in monitoring bioaccumulation of metals and metalloids in the South African endangered African grass-owl (Tyto capensis)

Few studies have quantified metals in South African species and no published data on residues specifically in South African owl feathers exist. Tyto capensis is listed as vulnerable within South Africa, making it preferable to use a non-invasive technique to determine metal bioaccumulation for this species. Comparisons are made with the cosmopolitan T. alba to determine whether this species could be used as a surrogate. Concentrations of various metals were thus determined in feathers of the two species and compared with liver and muscle samples. Samples were taken from 119 owls collected as road kill along a national road. A comparison of concentrations in feathers revealed similarly higher concentrations of aluminium, antimony, lead, nickel, and strontium, whereas concentrations of chromium, copper, iron, manganese, selenium, titanium and zinc were similarly higher in internal tissues for both species. Metal concentrations of owls were comparable to those reported in literature and below toxic levels, suggesting that these metals were not likely to impact the owls. Further regressions between feathers and corresponding livers were examined to determine if feathers were indicative of internal metal burdens. Significant positive relationships were found for aluminium, copper, lead, nickel and vanadium in T. alba and nickel, manganese and vanadium in T. capensis. Preliminary results support the feasibility of using feathers as non-destructive indicators of environmental contamination in T. capensis although caution needs to be taken when interpreting the results.http://link.springer.com/journal/1064

Pesticides in South African fresh waters

Public concern has recently escalated over pesticide contamination of South African aquatic ecosystems. This review of published literature on the occurrence of pesticides within South African freshwater systems indicates that fewer than 50 studies of selected pesticides have been undertaken, with emphasis being on organochlorines. Extensive historical usage has led to the widespread persistence of selected organochlorines. Few studies have established linkages between pesticides, exposure pathways, environmental concentrations and the monitoring of toxicological effects on non-target organisms. Emphasis is now being placed on developing more field-relevant assessments, including microcosm and mesocosm studies, in situ bioassays and field studies. There are few data relating to the extent of exposure and effects of pesticides in South African aquatic environments, and thus further research is needed. Research should focus on multidisciplinary approaches that increase effective decisionmaking in data-poor circumstances. A pesticide risk assessment programme for aquatic ecosystems needs to be implemented in South Africa, which could feed into the National Toxicity Monitoring Programme. Preliminary risk assessment models should be used to detect pesticides posing possible or definite risks, whereafter more detailed chemical, toxicological and biological monitoring assessments should be performed if risks are predicted