POCIS Calibration for Organic Compound Sampling in Small Headwater Streams.

Field-based atrazine sampling rates (Rs ) obtained by the polar organic chemical integrative sampler (POCIS) method were measured in 9 headwater streams over 3 yr covering 5 to 6 exposure periods of 2 to 3 wk/site/yr. Rates were best in line with the model Rs = 148 mL/d, with a standard deviation of 0.17 log units (factor 1.5). The POCIS canisters reduced mass transfer coefficients of the water boundary layer by a factor of 2 as measured by alabaster dissolution rates. A mechanistic model that accounts for flow and temperature effects yielded a fair estimate of the effective exchange surface area (12.5 ± 0.8 cm2 ). This model could only be tested for higher flow velocities because of uncertainties associated with the measurement of flow velocities <1 cm/s. Pictures of sorbent distributions in POCIS devices showed that the effective exchange surface area varied with time during the exposures. Error analysis indicated that sorbent distributions and chemical analysis were minor error sources. Our main conclusion is that an atrazine sampling rate of 148 mL/d yielded consistent results for all 3 yr across 9 headwater streams. Environ Toxicol Chem 2020;39:1334-1342. © 2020 SETAC.

Effects of formulation on transport of pyrethroids in residential settings.

Washoff of 17 pyrethroid products resulting from a 1-h, 25.4-mm rainfall occurring 24 h after application was measured in indoor studies with concrete slabs. These products included different pyrethroid active ingredients and a range of formulation types. Based on this replicated study, 5 product pairs with contrasting washoff behaviors were chosen for an outdoor study using 6 full-scale house fronts in central California. Products in 4 of these pairs were applied once to different rectangular areas on the driveway (1 product in each pair to 3 house lots and the other to the remaining 3 house lots). The products in the fifth pair were applied 3 times at 2-mo intervals to vertical stucco walls above the driveway. All house lots received natural and simulated rainfall over 7 mo. Indoor studies showed differences up to 170-fold between paired products, whereas the maximum difference between paired products in the field was only 5-fold. In the pair applied to the wall, 1 product had 91 times the washoff of the other in the indoor study, whereas in the field the same product had 15% lower washoff. These results show that, although the formulation may influence washoff under actual use conditions, its influence is complex and not always as predicted by indoor experiments. Because the formulation also affects insect control, washoff research needs to be conducted together with efficacy testing.

Integrative Medicine in Preventive Medicine Education: Competency and Curriculum Development for Preventive Medicine and Other Specialty Residency Programs.

During 2012, the USDHHS's Health Resources and Services Administration funded 12 accredited preventive medicine residencies to incorporate an evidence-based integrative medicine curriculum into their training programs. It also funded a national coordinating center at the American College of Preventive Medicine, known as the Integrative Medicine in Preventive Medicine Education (IMPriME) Center, to provide technical assistance to the 12 grantees. To help with this task, the IMPriME Center established a multidisciplinary steering committee, versed in integrative medicine, whose primary aim was to develop integrative medicine core competencies for incorporation into preventive medicine graduate medical education training. The competency development process was informed by central integrative medicine definitions and principles, preventive medicine's dual role in clinical and population-based prevention, and the burgeoning evidence base of integrative medicine. The steering committee considered an interdisciplinary integrative medicine contextual framework guided by several themes related to workforce development and population health. A list of nine competencies, mapped to the six general domains of competence approved by the Accreditation Council of Graduate Medical Education, was operationalized through an iterative exercise with the 12 grantees in a process that included mapping each site's competency and curriculum products to the core competencies. The competencies, along with central curricular components informed by grantees' work presented elsewhere in this supplement, are outlined as a roadmap for residency programs aiming to incorporate integrative medicine content into their curricula. This set of competencies adds to the larger efforts of the IMPriME initiative to facilitate and enhance further curriculum development and implementation by not only the current grantees but other stakeholders in graduate medical education around integrative medicine training.

Integrative Medicine in Preventive Medicine Education: Implementation Analysis.

In September 2012, the Health Resources and Services Administration funded 12 preventive medicine residency programs to participate in a 2-year project aimed at incorporating integrative medicine (IM) into their residency training programs. The grantees were asked to incorporate competencies for IM into their respective preventive medicine residency curricula and to provide for faculty development in IM. The analysis conducted in 2014-2015 used the following evidence to assess residency programs' achievements and challenges in implementation: progress and performance measures reports, curriculum mapping of program activities to IM competencies, records of webinar participation, and post-project individual semi-structured phone interviews with the 12 grantee project leaders. Key findings are: (1) IM activities offered to residents increased by 50% during the 2 years; (2) Accessing IM resources already in existence at local grantee sites was the primary facilitator of moving the integration of IM into preventive medicine residencies forward; (3) Among all activities offered residents, rotations were perceived by grantees as by far the most valuable contributor to acquiring IM competencies; (4) Online training was considered a greater contributor to preventive medicine residents' medical knowledge in IM than faculty lectures or courses; (5) Faculty were offered a rich variety of opportunities for professional development in IM, but some programs lacked a system to ensure faculty participation; and (6) Perceived lack of evidence for IM was a barrier to full program implementation at some sites. Grantees expect implemented programs to continue post-funding, but with decreased intensity owing to perceived faculty and curriculum time constraints.

Washoff of cypermethrin residues from slabs of external building material surfaces using simulated rainfall.

The use of pesticides by homeowners or pest-control operators in urban settings is common, yet contributions of washoff from these materials are not easily understood. In the present study, cypermethrin, formulated as Cynoff EC (emulsifiable concentrate) and Cynoff WP (wettable powder) insecticides, was applied at typical rates to 10 different building material surfaces to examine its washoff potential from each surface. Using an indoor rainfall simulator, a 1-h rainfall event was generated and washoff samples were collected from 3 replicates of each surface type. Washoff was analyzed for cypermethrin using gas chromatography-negative chemical ionization mass spectrometry. An analysis of variance for a split-plot design was performed. Many building materials had similar water runoff masses, but asphalt resulted in significantly reduced average water runoff masses (73% less). The Cynoff WP formulation generally produced greater cypermethrin washoff than the Cynoff EC formulation. In addition, results for both the WP and EC formulations indicated that smoother surfaces such as vinyl and aluminum siding had higher washoff (1.0-14.1% mean percentage of applied mass). Cypermethrin washoff from rough absorptive surfaces like concrete and stucco was lower and ranged from 0.1 to 1.3% and from 0 to 0.2%, respectively, mean percentage of applied mass. Both building material surface and formulation play a significant role in cypermethrin washoff.

Importance of colonization site in the current epidemic of staphylococcal skin abscesses.

OBJECTIVE: The goal was to compare rectal and nasal Staphylococcus aureus colonization rates and S aureus pulsed-field types (PFTs) for children with S aureus skin and soft-tissue abscesses and normal control subjects. METHODS: Sixty consecutive children with S aureus skin and soft-tissue abscesses that required surgical drainage and 90 control subjects were enrolled. Cultures of the nares and rectum were taken in both groups. S aureus isolates from all sites were characterized through multiple-locus, variable-number, tandem-repeat analysis, pulsed-field gel electrophoresis, staphylococcal cassette chromosome mec typing for methicillin-resistant S aureus isolates, and determination of the presence of Panton-Valentine leukocidin genes. RESULTS: S aureus was detected significantly more often in the rectum of children with abscesses (47%) compared with those in the control group (1%; P = .0001). Rates of nasal colonization with S aureus were equivalent for children with abscesses (27%) and control subjects (20%; P = .33). S aureus recovered from the rectum was identical to S aureus in the abscess in 88% of cases, compared with 75% of nasal isolates. PFT USA300, staphylococcal cassette chromosome mec type IV, and Panton-Valentine leukocidin genes were significantly increased in the S aureus isolates from children with abscesses compared with those from control subjects. CONCLUSIONS: Skin and soft-tissue abscesses in the current epidemic of community-associated staphylococcal disease are strongly associated with rectal colonization by PFT USA300. Nasal colonization in children does not seem to be a risk factor.

Overland and near-surface transport of Cryptosporidium parvum from vegetated and nonvegetated surfaces.

Understanding microbial pathogen transport patterns in overland flow is important for developing best management practices for limiting microbial transport to water resources. Knowledge about the effectiveness of vegetative filter strips (VFS) to reduce pathogen transport from livestock confinement areas is limited. In this study, overland and near-surface transport of Cryptosporidium parvum has been investigated. Effects of land slopes, vegetation, and rainfall intensities on oocyst transport were examined using a tilting soil chamber with two compartments, one with bare ground and the other with brome (Bromus inermis Leyss.) vegetation. Three slope conditions (1.5, 3.0, and 4.5%) were used in conjunction with two rainfall intensities (25.4 and 63.5 mm/h) for 44 min using a rainfall simulator. The vegetative surface was very effective in reducing C. parvum in surface runoff. For the 25.4 mm/h rainfall, the total percent recovery of oocysts in overland flow from the VFS varied from 0.6 to 1.7%, while those from the bare ground condition varied from 4.4 to 14.5%. For the 63.5 mm/h rainfall, the recovery percentages of oocysts varied from 0.8 to 27.2% from the VFS, and 5.3 to 59% from bare-ground conditions. For all slopes and rainfall intensities, the total (combining both surface and near-surface) recovery of C. parvum oocysts was considerably less from the vegetated surface than those from the bare-ground conditions. These results indicate that the VFS can be a best management practice for controlling C. parvum in runoff from animal production facilities.