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Abstract: PM10, which is considered among the major indoor and outdoor pollutants, was measured in several residential homes and corresponding outdoor environments in the Great Beirut area over the summer and winter seasons of 2005. Few studies on PM10 levels indoors in Beirut are restricted to short-term periods in public places. In this study, 78 PM10 samples were collected on Teflon filters using an active sampler at a flow rate of 5 L/min. PM10 mass concentrations were determined by gravimetric analysis, and inorganic chemical speciation was carried out using ion chromatography. Outdoors, PM10 elevated mass concentrations correlated well with high traffic density. The observed high intra-site temporal variation (minimum of 34 and a maximum of 120 μg/m3) was attributed to the dynamic air masses passing over the Eastern Mediterranean region. Indoors, PM10 levels were highly affected by outdoor levels, but were enhanced over those of outdoors when smoking activities were recorded. In winter, the overall average outdoor concentration dropped by 19%, whereas the average indoor concentration increased by 50% over the ones calculated for the summer. Ventilation and air exchange rates were found to be approximately equal to unity during summer since most doors and windows remain open. This rate drops to almost half during winter. As for particulate ions namely nitrates and sulfates, the former showed concentrations that are higher than the values reported in the region in both winter and summer seasons, suggesting high emissions from local vehicles. However, SO4 2− average concentrations were comparable to values reported in other studies conducted in Eastern Mediterranean sites. Soluble particulate nitrates and sulfates exhibited similar indoor and outdoor levels in non-smoking homes (IO~1), but in smoking homes the drop in nitrate concentrations reached around 70%, indicating a high anionic reactivity with tobacco smokes. [Copyright &y& Elsevier]

Plastic made with bisphenol A (BPA) produces trans-generational changes in genes and behavior. It has been positively linked to obesity and thyroid dysfunction. This study aimed to detect the presence of BPA in polycarbonate plastic (PC) baby bottles. Fifteen PC baby bottles with a clear indication of BPA free/safe/clear were randomly selected. High-performance liquid chromatography (HPLC) tests were used to detect residual or migrating BPA post three stress tests. An estimated intake of BPA among children was calculated then compared to the universal tolerable daily intake (TDI). Around 27% of bottles had detectable amounts of residual BPA in the first test, 100% released migrating BPA in the second and third tests. A significant positive linear trend in migrated BPA levels was observed over the three consecutive tests P < 0.0001. Approximately 73.5% of the accounted variability in BPA levels was due to these stress tests P < 0.0001. Babies from 0 to 3 months are expected to consume 0.8 to 23.8% of their safe TDI of BPA just by using plastic bottles between the first time of usage and after 60 washes (estimated 15 to 20 days of usage). Although no bottles have shown a risk of BPA intake exceeding TDI, the combined use of BPA bottles with other plastic utensils might result in reaching it. It is advisable to refrain from using BPA-containing plastic bottles or be cautious about usage duration. Manufacturers should indicate a clear margin of usage duration. Four baby bottle brands showed the least BPA leaking (Baby King, Camera, Sweet Baby, and Farlin).

The reaction of [Ru(arene)Cl(2)](2) (arene = benzene, p-cymene) with [X(2)W(22)O(74)(OH)(2)](12-) (X = Sb(III), Bi(III)) in buffer medium resulted in four organo-ruthenium supported heteropolytungstates, [Sb(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (1), [Bi(2)W(20)O(70)(RuC(6)H(6))(2)](10-) (2), [Sb(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (3), and [Bi(2)W(20)O(70)(RuC(10)H(14))(2)](10-) (4), which have been characterized in solution by multinuclear ((183)W, (13)C, (1)H) NMR, UV-vis spectroscopy, electrochemistry, and in the solid state by single-crystal X-ray diffraction, IR spectroscopy, thermogravimetric analysis, and elemental analysis. Polyanions 1, 2, and 4 crystallize in the triclinic system, space group P1 with the following unit cell parameters: K(5)Na(5)[Sb(2)W(20)O(70)(RuC(6)H(6))(2)] x 22 H(2)O (KNa-1), a = 12.1625(2) A, b = 13.1677(2) A, c = 16.0141(3) A, alpha = 78.9201(7) degrees, beta = 74.4442(8) degrees, gamma = 78.9019(8) degrees, and Z = 1; Cs(2)Na(8)[Bi(2)W(20)O(70)(RuC(6)H(6))(2)] x 30 H(2)O (CsNa-2), a = 11.6353(7) A, b = 13.3638(7) A, c = 16.7067(8) A, alpha = 79.568(2) degrees, beta = 71.103(2) degrees, gamma = 80.331(2) degrees, and Z = 1; Na(10)[Bi(2)W(20)O(70)(RuC(10)H(14))(2)].35H(2)O (Na-4), a = 15.7376(12) A, b = 15.9806(13) A, c = 24.2909(19) A, alpha = 92.109(4) degrees, beta = 101.354(4) degrees, gamma = 97.365(3) degrees, and Z = 2. Polyanions 1-4 consist of two (L)Ru(2+) (L = benzene or p-cymene) units linked to a [X(2)W(20)O(70)](14-) (X = Sb(III), Bi(III)) fragment via Ru-O(W) bonds resulting in an assembly with idealized C(2h) symmetry. Polyanions 1-4 are stable in solution as indicated by the expected (183)W, (13)C, and (1)H NMR spectra. The electrochemistry of 1-4 is described by considering the reduction and the oxidation processes. The nature of the arene in Ru(arene) has practically no influence on the formal potentials of the W-centers, which are more sensitive to the Sb or Bi hetero atoms. The results suggest that the respective Sb- and Bi derivatives have very different pK(a) values, with the reduced form of 1 being the most basic, thus permitting the observation of two well-developed voltammetric waves at pH 6. In contrast, the identity of the arene influences the oxidation processes, thus permitting to distinguish them. A strong electrocatalytic water oxidation peak is observed that is more positive than the one corresponding to the Ru(arene) oxidation process. Also a stepwise oxidation of the Ru(benzene) group could be observed at pH 3. The catalytic efficiency, on the other hand, of 1-4 toward the oxidation of n-hexadecane and p-xylene illustrated the effect of ruthenium substitution on the polyanion catalytic performance.