Trace element composition of aqueous extracts of some diatomite and lydite samples from Karelia

Актуальность исследования обусловлена необходимостью получения достоверной информации об элементном составе водных экстрактов диатомитов и лидитов. В настоящее время диатомиты используются в различных отраслях промышленности, в том числе медицинской и фармацевтической. Однако детального изучения состава их водных экстрактов практически не проводилось. Цель: изучить микроэлементный состав водных экстрактов нескольких образцов диатомитов и лидитов. Объекты: три образца диатомитов и два образца лидитов территории Республики Карелия. Методика: лабораторный эксперимент, водная экстракция, масс-спектрометрия с индуктивно-связанной плазмой (ICP MS). Результаты. Изучен элементный состав водных экстрактов нескольких образцов диатомитов и лидитов территории Республики Карелия методом ICP MS. Во всех исследованных экстрактах образцов диатомитов и лидитов преобладающими элементами являются Mg, Na, Ca, K и Al (до нескольких тысяч мкг/л). Экстракты образцов диатомитов имеют однородный состав. Максимальные содержания в них других, наиболее значимых, элементов составляли: P - до 650, Fe - до 1700 (образец № 1) и Mn - до 3300 (образец № 3) мкг/л. Концентрации в диапазоне от 10 до 100 мкг/л характерны для ряда элементов (Li, B, Ti, Cr, Co, Ni, Cu, Zn, Sr, Y, Zr и Ba) в экстрактах всех образцов диатомитов. Экстракты образцов диатомитов № 1 и 2 имели максимальные концентрации легких редкоземельных элементов (РЗЭ): Nd (до 247), Ce (до 230), La (до 156 мкг/л). Химический состав экстрактов образцов лидитов заметно отличался, как между собой, так и от экстрактов диатомитов. Кислая среда (рН 4,5-4,6) экстракта образца № 4 способствовала накоплению ряда элементов: Ni, Sr, Be, Mn, U, Tl, и особенно V, Co, Cu, Zn, Y, Ba. В то же время в экстракте образца № 5 в слабощелочных условиях (рН 7,4-7,5) наблюдались максимальные концентрации Mo, W, Zr, Hf. В исследованных экстрактах образцах диатомитов и лидита № 4 концентрации Al, Mn, Fe, Co, Ni, Cu, Zn превышали значения предельно допустимых концентраций (ПДК) рыбохозяйственных водоемов. Водные экстракты образцов диатомитов показали значительное содержание элементов, которые могут оказать влияние на формирование состава маломинерализованных карельских вод. При этом содержание ряда полезных для развития растений микроэлементов (Ca, Mg, К, Р, Cu, Zn, V, Mn, Sr, Y, Zr) предполагает возможность их использования как «мягких» удобрений (или добавок к минеральным удобрениям).The relevance of the research consists in the necessity to obtain reliable information on microelemental composition of aqueous extracts of diatomite and lydite. Currently, diatomites are expected to be widely used in medical, pharmaceutical and food industries, but a detailed study of their composition has not been conducted. The main aim of the research is to investigate the trace element composition of aqueous extracts of several samples of diatomite and lydite using ICP MS analytic method. The objects: three samples of diatomite and two samples of lydite from Karelia (North-West of Russia). Methods: grinding samples of diatomite and lydite infused with deionized water at room conditions. Assays of aqueous extracts of the studied samples were centrifuged and analyzed by ICP MS after 1, 3 and 10 days. Results. The authors present the results of 54 chemical elements identification in water extracts of diatomite and lydite using ICP MS. In all water extracts Mg, Na, Ca, K and Al (up to several thousand µg/l) are the predominant elements. Extracts of diatomite samples have a more homogeneous composition. The most important elements were: P - 650, Fe - 1700 (sample no. 1) and Mn - up to 3300 (sample no. 3) µg/L. Concentrations in the range from 10 to 100 µg/l are typical for a number of elements (Li, B, Ti, Cr, Co, Ni, Cu, Zn, Sr, Y, Zr and Ba) of all diatomite samples. Extracts of diatomite samples no. 1 and 2 had a maximum concentration of light REE: Nd (up to 247 µg/l), Ce (up to 230 µg/l), La (up to 156 µg/l). Chemical composition of extracts of lydite was differed markedly, both among themselves and from diatomites. Acidic medium (pH 4,5-4,6) of an aqueous extract of the sample lydite no. 4 contributed to accumulation of a number of elements Sr, Mn, U and, especially, Be, Fe, Co, Ni, Cu, Zn, Y, Ba, Tl. At the same time, maximum concentrations of V, Mo, W, Zr, Hf were observed in the extract of sample no. 5 under slightly alkaline conditions (pH 7,4-7,5). We noted an excess of permissible limits of fishery water bodies for Al and Mn in all samples. The excess of the «normal» maximum permissible concentrations have also shown the transition elements (Fe, Co, Ni, Cu, Zn) in extracts of diatomite and sample lydite no. 4, as well as V and Mo in the sample lydite no. 5. The study of aqueous extracts of diatomite and lydites showed that diatomite and lydites under certain conditions can have a significant impact on composition of low-mineralized waters in the territory of Karelia. At the same time, the presence of useful elements for the plant growth (Mg, Ca, K, Cu, Zn, V, Mn, Sr, Y, Zr) gives the possibility of their use as a «soft» fertilizers (or additives to mineral fertilizers)

Cardiopulmonary resuscitation in adults over 80 : outcome and the perception of appropriateness by clinicians

OBJECTIVES: To determine the prevalence of clinician perception of inappropriate cardiopulmonary resuscitation (CPR) regarding the last out‐of‐hospital cardiac arrest (OHCA) encountered in an adult 80 years or older and its relationship to patient outcome. DESIGN: Subanalysis of an international multicenter cross‐sectional survey (REAPPROPRIATE). SETTING: Out‐of‐hospital CPR attempts registered in Europe, Israel, Japan, and the United States in adults 80 years or older. PARTICIPANTS: A total of 611 clinicians of whom 176 (28.8%) were doctors, 123 (20.1%) were nurses, and 312 (51.1%) were emergency medical technicians/paramedics. RESULTS AND MEASUREMENTS: The last CPR attempt among patients 80 years or older was perceived as appropriate by 320 (52.4%) of the clinicians; 178 (29.1%) were uncertain about the appropriateness, and 113 (18.5%) perceived the CPR attempt as inappropriate. The survival to hospital discharge for the “appropriate” subgroup was 8 of 265 (3.0%), 1 of 164 (.6%) in the “uncertain” subgroup, and 2 of 107 (1.9%) in the “inappropriate” subgroup (P = .23); 503 of 564 (89.2%) CPR attempts involved non‐shockable rhythms. CPR attempts in nursing homes accounted for 124 of 590 (21.0%) of the patients and were perceived as appropriate by 44 (35.5%) of the clinicians; 45 (36.3%) were uncertain about the appropriateness; and 35 (28.2%) perceived the CPR attempt as inappropriate. The survival to hospital discharge for the nursing home patients was 0 of 107 (0%); 104 of 111 (93.7%) CPR attempts involved non‐shockable rhythms. Overall, 36 of 543 (6.6%) CPR attempts were undertaken despite a known written do not attempt resuscitation decision; 14 of 36 (38.9%) clinicians considered this appropriate, 9 of 36 (25.0%) were uncertain about its appropriateness, and 13 of 36 (36.1%) considered this inappropriate. CONCLUSION: Our findings show that despite generally poor outcomes for older patients undergoing CPR, many emergency clinicians do not consider these attempts at resuscitation to be inappropriate. A professional and societal debate is urgently needed to ensure that first we do not harm older patients by futile CPR attempts. J Am Geriatr Soc 68:39–45, 201