Heavy metals burden of Keenjhar Lake, District Thatta, Sindh, Pakistan

Detection of heavy metals (HMs) content from Keenjhar Lake water was carried out monthly from January to December, 2003. Zinc, chromium, copper, iron, manganese, nickel and cadmium were analyzed by dual mode of analytical methods flame atomic absorption spectrometry and electrothermal atomic absorption spectrometry (FAAS and ETAAS) by multi element standard solution. The concentrations of zinc, chromium, copper, iron, manganese Nickel and cadmium were 1.4 to 104.3 μgL-1, 1.28 to 4.9 μgL-1, 0.6 to 7.3 μgL-1, 2 to 45.6 μgL-1, 0.2 to 6.7 μgL-1, 3.54 to 39.5 μgL-1 and 1.0 to 4.3 μgL-1, respectively. Zn2+, Cr+, Cu2+, Fe2+ and Mn2+ concentrations were recorded lower than those of permissible limits, whereas Ni+ and Cd+ were higher than those of permissible limits recommended by WHO (2004).Key words: Heavy metals, Keenjhar Lake, toxicity

Quantum gravitational corrections for spinning particles

We calculate the quantum corrections to the gauge-invariant gravitational potentials of spinning particles in flat space, induced by loops of both massive and massless matter fields of various types. While the corrections to the Newtonian potential induced by massless conformal matter for spinless particles are well-known, and the same corrections due to massless minimally coupled scalars [Class. Quant. Grav. 27 (2010) 245008], massless non-conformal scalars [Phys. Rev. D 87 (2013) 104027] and massive scalars, fermions and vector bosons [Phys. Rev. D 91 (2015) 064047] have been recently derived, spinning particles receive additional corrections which are the subject of the present work. We give both fully analytic results valid for all distances from the particle, and present numerical results as well as asymptotic expansions. At large distances from the particle, the corrections due to massive fields are exponentially suppressed in comparison to the corrections from massless fields, as one would expect. However, a surprising result of our analysis is that close to the particle itself, on distances comparable to the Compton wavelength of the massive fields running in the loops, these corrections can be enhanced with respect to the massless case