Lead, mercury, and certain nutrient elements in ulva lactuca (linnaeus) from Ras Beirut, Lebanon

Abstract

Collections of Ulva lactuca (Linnaeus) at nine locations along the coast of Ras Beirut, Lebanon were analysed for lead, mercury, phosphate, calcium, magnesium, iron, copper, and zinc . Low lead concentrations, the same in all samples, could possibly indicate that U. lactuca has some means by which lead uptake and toxicity can be controlled . Phosphate levels may be a contributing factor to this process .Concentrations of all other elements seemed relatively uniform with few exceptions. This suggests that U. lactuca is subject to similar environmental conditions and element exposure at each of the collecting sites and might be capable of maintaining biochemical stability under high levels of stress .Further studies of toxic and nutrient elements as to their individual and combined effects in U. lactuca are needed .

Trace metals with seasonal considerations in coastal algae and molluscs from Beirut, Lebanon

“…Cadmium was also variable. The lead, iron, copper and zinc concentrations reported here for U. lactuca are much higher than the values found in the same species collected on the coast of Ras Beirut in the summer of 1975 and analysed at the American University of Beirut Hospital Laboratory (Shiber & Washburn, 1978). It would appear that the levels being reported in the present work might be more representative of the actual situation, especially in relation to the values found in the other species of algae analysed on three separate occasions.…”

“…U. lactuca was again flourishing in mid-April. It seems that this species experiences several 'peaks' of growth within the year in Ras Beirut (Shiber & Washburn, 1978).…”

Metal accumulation in a biological indicator (Ulva rigida) from the lagoon of Venice (Italy)

“…In particular, the studies of Hggherall (1973), Shiber and Washburn (1978), Sawidis and Voulgaropoulos (1986), and Ho (1990), support the existence of a direct relationship between metal concentrations in water and in the tissues of U. lactuca.…”

“…Since alkaline pH makes Pb insoluble (Shiber and Shatila 1979) and thus unavailable to algae, some other factors probably induce the bioavailability of Pb. In U. lactuca, phosphate may act as a control mechanism, either decreasing the toxicity of Pb or controlling its uptake (Shiber and Washburn 1978); so an increase in Pb concentration may be due to a reduction in phosphate levels. The absorption of A1 also increases when phosphorus (P) decreases, because in phosphorus-rich media A1 precipitates in form of aluminium-phosphate (Greger et al 1992).…”

Certain metals in three coastal algae from Ras Beirut waters

“…In comparison to levels found in another green alga, Ulva lactuca (Linnaeus), taken from the approximate same locations in July and August, 1975(Shiber & Washburn, 1978, the copper and iron concentrations in H. tuna were much higher, and lead was also higher Colpomenia sinuosa seemed to concentrate rather high levels of lead compared to levels found in other species of brown algae from various parts of the world (Black & Mitchell, 1952;Stenner & Nickless, 1975 ;Bradfield et al, 1976 ;Seeliger & Edwards, 1977). Cadmium in this alga was either slightly lower than some reported levels for other species (Nickless et al, 1972 ;Stenner &Nickless, 1975 ;Bradfield et al, 1976), or within a similar range (Dutton et al, 1973 ;Leatherland & Burton, 1974;Lande, 1977 ;Bryan & Hummerstone, 1977), whereas copper, nickel and especially iron appeared to be relatively high (Black & Mitchell, 1952 ;Preston et al, 1972 ;Dutton et al, 1973 ;Bradfield et al, 1976 ;Bryan & Hummerstone, 1977) .…”