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The oxidation of As(III) to As(V) by K-birnessite was examined at different temperatures, pHs, and birnessite/As(III) ratios. Experiments ranged in duration from 5 to 64 hr, and solution and solid products were determined at several intervals. All experiments showed that the reaction produced large amounts of K+ to solution and very little Mn2+. As(V) was released to solution and incorporated into the K-birnessite. The oxidation was initially rapid and then slowed. The oxidation of As(III) was probably facilitated initially by autocatalytic Mn-As(V) reactions occurring mostly in the interlayer, in which large amounts of As(V) and K+ could be easily released to solution. The reaction also slowed when interlayer Mn was exhausted by forming Mn-As(V) complexes. Mn(IV) could only be acquired from the octahedral sheets of the birnessite. The two-stage reaction process proposed here depended on the layered structure of birnessite, the specific surface, and presence of exchangeable cations in K-birnessite.

The frequent use of marijuana by American youth has compelled the Committee on Drugs to explore the present methods of and recommendations for controlling marijuana. On October 15, 1970, the Executive Board of the American Academy of Pediatrics endorsed in principle a statement on marijuana which was prepared by the Massachusetts Chapter of the Academy and published in the Academy's Newsletter.1 This statement called for considering possession of marijuana as a misdemeanor rather than a felony, but it was against legalizing use of marijuana at the present time. On October 27, 1970, President Nixon signed into law the Comprehensive Drug Abuse, Prevention and Control Act of 1970 (P.L. 91-513). This law became effective May 1, 1971; it is the Federal Government's attempt to control drug abuse by scientific and medical measures (under control of the Department of Health, Education, and Welfare) and by law enforcement activities (Department of Justice). The new Federal law has stopped short of legalizing marijuana, but it does allow a judge the discrelion to withhold criminal charges for the first offense of possession. The Massachusetts Chapter notes2 that marijuana is not a narcotic and does not produce addiction. Short-term physical effects are innocuous. However, impaired performance on simple intellectual and psychomotor tests is seen after individuals have smoked marijuana for the first time; but, such effects are not seen in regular users. There is no evidence to substantiate the common misconceptions that use of marijuana leads to crime or addiction to opiates. But, so little scientific information is available on the long-term use of marijuana that it should be considered a potentially harmful drug.

When broad-spectrum antibiotics were first introduced two decades ago for the treatment of acne, justification for such therapy seemed reasonably straightforward, e.g., the suppression of the suppurative inflammatory lesions commonly encountered in acne. As time went on, however, certain observations raised questions concerning the rationale for this form of treatment. First, it became apparent with cumulative clinical experience that the disease could ordinarily be controlled by doses of antibiotics lower than those required to treat bacterial infections. Second, bacteriologic studies disclosed that the only bacteria regularly recoverable from acne lesions were the anaerobic diphtheroid Corynebacterium acnes and aerobic coagulase-negative cocci, predominantly staphylococcus type II; both of these bacteria are known to be normal resident skin organisms.1 Thus, as no reports of controlled studies were then available for assessing the true efficacy of antibiotics used in the treatment of acne, the uneasy suspicion arose that such therapy might be inducing a primarily placebo response. In 1965, Freinkel and her collaborators2 demonstrated that the oral administration of tetracycline, even in doses as small as 250 mg daily, resulted in a significant reduction of the free fatty acid concentration of the lipid (sebum) secreted to the skin surface by the sebaceous glands. This effect could be observed in normal subjects as well as in patients with acne and was entirely reversible on discontinuance of drug. The inflammatory lesions of acne are known to result from disorganization of the follicular epithelium, with consequent liberation of the intrafollicular contents, containing sebum, into the dermis.3