Tar pollution event (2021) at the Southeastern Levantine oligotrophic basin, short-term impacts and operational oceanography perspectives.

The Levantine basin (LB) in the Southeastern Mediterranean Sea is a high-risk oil pollution hot spot owing to its dense maritime traffic and intense oil and gas exploration and exploitation activities. In February 2021 the Israeli LB shorelines were impacted by an exceptional tar pollution event (~550 tons; average distribution: ~3 kg tar m-1 front beach) of an unknown oil spill source. Here we report on the immediate numerical modelling assessment of the oil spill propagation and tar distribution; operational use of underwater gliders for tracking water column anomalies of dissolved polycyclic aromatic hydrocarbons (PAHs) and turbidity signals; the beached tar composition and amounts and the short-term response of the microbial population along the ~180 km shoreline. This pollution event emphasizes the need for improving the early warning systems for oil spills and implementing continuous operational monitoring at high-risk, ecologically sensitive and valuable resource areas like the Israeli LB waters.

Downwind gas condensate volatiles affect phytoplankton communities.

We investigated the effects of volatile organic carbons (VOCs) evaporated from gas condensate on the cyanobacteria Synechococcus sp. WH8103, the diatom Asterionellopsis glacialis, and the dinoflagellate Alexandrium minutum. We used custom algal incubation chambers enabling only the gas condensate-derived VOCs to interact with the cell cultures via an atmospheric bridge, without direct contact with the hydrocarbon oil. The exposure to gas condensate VOCs reduced the abundance, growth rate, and photosynthetic efficiency of Synechococcus sp. WH8103. Thiobarbituric acid reactive substances (TBARS) assays hint at oxidative damage to the chloroplasts and/or the thylakoid membranes in this organism. A.glacialis abundance, physiological state and growth rates remained unchanged, whereas A.minutum abundance and photosynthetic efficiency increased relative to their respective controls. Our results demonstrate that the effects of a gas condensate formed due to an oil spill will not be restricted to the polluted area, but may be prominent in downwind locations through atmospheric transport.

M-CSF and GM-CSF regulation of STAT5 activation and DNA binding in myeloid cell differentiation is disrupted in nonobese diabetic mice.

Defects in macrophage colony-stimulating factor (M-CSF) signaling disrupt myeloid cell differentiation in nonobese diabetic (NOD) mice, blocking myeloid maturation into tolerogenic antigen-presenting cells (APCs). In the absence of M-CSF signaling, NOD myeloid cells have abnormally high granulocyte macrophage colony-stimulating factor (GM-CSF) expression, and as a result, persistent activation of signal transducer/activator of transcription 5 (STAT5). Persistent STAT5 phosphorylation found in NOD macrophages is not affected by inhibiting GM-CSF. However, STAT5 phosphorylation in NOD bone marrow cells is diminished if GM-CSF signaling is blocked. Moreover, if M-CSF signaling is inhibited, GM-CSF stimulation in vitro can promote STAT5 phosphorylation in nonautoimmune C57BL/6 mouse bone marrow cultures to levels seen in the NOD. These findings suggest that excessive GM-CSF production in the NOD bone marrow may interfere with the temporal sequence of GM-CSF and M-CSF signaling needed to mediate normal STAT5 function in myeloid cell differentiation gene regulation.

Gowns: selection on a procedure-driven basis.

The Occupational Safety and Health Administration requires that the types and characteristics of personal protective equipment used "depend upon the task and degree of exposure anticipated." The level of protection required, therefore, is logically contingent upon the operative site, estimated blood loss, and duration of the procedure. However, more recent studies provide data that specifically identify the personnel and areas of the body that are most likely to become contaminated. This adds a new dimension to the procedure-oriented selection process that is worthy of consideration.

The evolution of the surgical mask: filtering efficiency versus effectiveness.

When originally introduced for use at the turn of the century, the primary function of the surgical mask was to prevent the migration of microorganisms residing in the nose and mouth of members of the operating team to the open wound of the patient. As technology developed new materials and designs, their filtering efficiencies gradually improved. However, there is no standard test method for assessing that capability, and its influence on the rates of surgical-wound infection has yet to be demonstrated. Quite to the contrary, both in-vitro and in-vivo studies indicate that a mask may not be universally necessary in today's surgical environment.

Home laundering of soiled surgical scrubs: surgical site infections and the home environment.

An increasing number of hospitals have implemented programs that permit their operating room (OR) personnel to launder their soiled "scrubs" at home. Not only have they not experienced an increase in the incidence of surgical site infections (SSIs), but they have also found the policy to be financially rewarding. Whereas the Association of periOperative Registered Nurses (AORN) opposes the practice, the Centers for Disease Control and Prevention (CDC) describes it as an unresolved issue. The variances in the positions taken by these two organizations obviously accounts for the differences in positions taken by the infection control community. In the absence of any evidence in the literature, the only alternative is to draw from knowledge and experience to determine whether the practice can be considered clinically effective and does not have a harmful effect on the home environment. On the basis of the results of that examination, it is concluded that the need for having soiled scrubs laundered by a facility-approved laundry is indefensible and simply predicated on the "that's the way we've always done it" syndrome.

Surgical gowns and drapes as aseptic barriers.

The use of surgical gowns and drapes has become the standard of practice in the arena of surgical aseptic technique. Because of myriad of materials, both woven and nonwoven, are currently available, users are faced with the difficult task of choosing a bacteriologic barrier material that is effective, safe, and economical. Although recommendations are available for general selection and use of barrier materials, no specific guidelines exist to assist the user in evaluating the important features of barriers. In addition, standards are lacking for safety characteristics such as flammability and fiber content. The infection control practitioner needs to be aware of the issues surrounding surgical barrier materials to be able to put the infection control merits of these materials in their proper perspective.

Use of scrubs and related apparel in health care facilities.

There is no scientific evidence that the use of scrubs or other related apparel contributes to either the cause or the prevention of infections associated with health care facilities. However, because this type of apparel is now used so commonly as a replacement for the more traditional type of uniform, its original function as an ensemble worn by surgical personnel no longer prevails. The variety of these applications actually raises a new series of issues and challenges that would be best resolved by a multidisciplinary health care group with representatives from administration, nursing, medicine, materials management, human resources, infection control, and other affected departments. The purpose of this report is to facilitate this process.

Aseptics and aesthetics of chlorine bleach: can its use in laundering be safely abandoned?

The disinfecting and cleansing properties of chlorine bleach in high-temperature laundering formulations first was demonstrated in 1938, and subsequently was found to be equally effective in lower-temperature formulations that included modifications in the laundering cycle. Until another well-documented bleaching additive becomes commercially available, chlorine bleach should continue to be an integral part of the laundering formulations for all textiles used in health care facilities.

Testing surgical gowns for the "anticipated level of exposure".

Although the use of the surgeon's gown dates back to the turn of the century, the need for it to be made of a liquid-repellent material was disclosed only in 1952. Because of the relatively poor performance of the products that were introduced early on, the entire textile industry--makers of nonwoven disposable and woven reusable materials alike--was challenged to develop a test method to demonstrate a fabric's capability "under usual conditions of use." A cooperative attempt to do that was abandoned in 1983. With the emergence of HIV, the need to protect the wearer became the gown's priority. However, because there was no standard test method, the manufacturers used any of an array of tests to promote a product's suitability for use under what the Occupational Safety and Health Administration describes as the "level of exposure anticipated." Now, a standard test method has been adopted that describes the results on a pass/fail basis. However, the literature indicates that gowns made of materials that have passed this test have failed "under usual conditions of use." Nevertheless, the Food and Drug Administration is permitting manufacturers to mislead the surgical community by describing products as being "impervious" or "liquid proof."

Barrier materials. Their influence on surgical wound infections.

Aseptic technique can best be described as an aggregation of reasonable practices performed in the surgical suite as part of the overall methodology in controlling or minimizing the possibility of infection. The key words in this definition are aggregation and reasonable. The real question is whether the surgical nursing community is prepared to reconsider and reassess the importance of a theoretical and reasonable, but not proven, practice that it has been advocating for almost two decades. From the evidence, it appears that a departure from the universal application of the barrier principle would not compromise the quality of care rendered to the surgical patient while at the same time prove to be economically and environmentally advantageous.

OR barrier materials--necessity or extravagance?

The issue at hand, therefore, is not one of reusable versus disposable, but rather the cost-effectiveness and expense associated with use of barrier versus nonbarrier materials. As mandated by the Occupational Safety and Health Administration, the need and function of the surgeons' gown barrier is a given. Initially the gown was used to protect the patient from members of the surgical team; its role now is to protect the surgical team members from the patient and the hazards associated with exposure to bloodborne pathogens. As for barrier drapes (i.e., patient, Mayo stand, back table covers), considering the influence of today's antibiotics and the advent of minimally invasive surgical techniques on the incidence of postoperative infection, just how necessary are they? Initially the use of barrier drapes was viewed as a reasonable practice. The problem, however, with any reasonable type of practice of this nature is identifying the kind and quality of supporting evidence and testing the practice itself. If there is no evidence for or against a practice; its advocates make up the process as they go along. In the case of barrier drapes, there were individuals who assumed that there were studies that conclusively demonstrated their need, even though they never sought confirmation to that effect. In the process, whether the drapes were cost-effective escaped criticism, and their use survived over the years because of the "that's the way we've always done it" syndrome. In a comprehensive examination of draping practices written 60 years ago, a physician discusses the myriad sources of contamination that could contribute to postoperative infection. He concluded that "to minimize the chances of contamination, all of these sources must be separately and individually studied." In terms of the influence of barrier surgical drapes, there remains a need for unbiased, statistically valid, conclusive research. Until such data become available, their use cannot be indisputably defended.