The effects of salinity upon the growth, photosynthesis, ion and water contents of a population of Dactyloctenium aegyptium originating from a saline site in Nigeria were investigated. Growth was unaffected by a salinity of 10% artificial sea water, but was reduced by one third in 20% and by two thirds in 30% artificial sea water respectively. Initial adjustment to salinity was due both to increases in the concentrations of sodium and potassium per unit dry weight and to reduced hydration, the latter being the more important at higher salinities. The increase in ion concentration in the cell sap balanced the salinity of the medium at 10% artificial sea water, but was excessive at higher concentrations of sea water. Net photosynthesis was unaffected by 10% artificial sea water but declined at higher salinities. The potassium content of the plants did not fall below 200–250 mM, and the sodium to potassium ratio did not exceed three, even at the highest salinities. Variation in the concentration of nutrients (potassium, nitrate and sulphate) in the medium in the presence of 25% artificial sea water had significant effects upon growth, but these were small in relation to the inhibitory effect of the salinity.The reduction in growth could not be attributed to lack of osmotic adjustment or to nutrient deficiency, and was probably due to ion toxicity within the leaves. The tolerance to reduced hydration, combined with the ability to germinate in saline conditions previously observed, could enable D. aegyptium to establish in a saline soil. The population did not exhibit any halophytic characteristics but did survive with a low growth rate at salinities up to 50% artificial sea water. It is concluded that the species was able to colonize the saline site because of its inherent adaptability, rather than the possession of an ecotype adapted to saline conditions.

Consumption of food contaminated with heavy metals is a major source of health problems for man and animals. Three commonly edible Leafy vegetables (Amaranthus hybridus, Celosia argentea ,Cochorus olitoris) from Agboju and Iba markets , Lagos Nigeria were sampled, identified, digested and analyzed with the aid of Atomic Absorption Spectrophotometer (AAS) as directed by APHA (American Public Health Association) to determine heavy metals concentration in them with the aim of ascertaining their edibility for human consumption. The mean concentration for each heavy metal in the samples gotten from each market were calculated, the comparison of these data was done amongst the two markets, and compared with the permissible levels set by the FAO and WHO. The results showed that the levels of Lead, Cadmium, Copper, Zinc, Iron, Nickel, Selenium and Chromium present in the vegetable concentrated in the following order Fe>Pb>Zn>Cd>Ni>Cu>Cr>Se. With regards to vegetables in questions, analysis of variance showed that some vegetables accumulated metals more than each other and as such indicated that metals like copper, cadmium, selenium, iron and zinc are significant at P<0.05) while others were not. Whereas with regards to locations, Iron, cadmium and lead were significant at P< (0.05) while other metals were not significant P>0.05). With significant values of lead, cadmium and nickel, recorded in both Amaranthus hybridus and Celosia argentea vegetables, vegetables consumers must be weary of vegetables to buy and the market that is save to buy from, especially markets located very close to highways or close to major busy roads .

The effects of three traditional smoking methods on the concentrations of Polycyclic Aromatic Hydrocarbons (PAHs) in smoked fishes were studied to determine the concentration of PAHs in locally available and commonly consumed smoked fish species. Samples of two highly traded species of fish, Scomber scombrus and Horse markerel, among the low income people for immediate consumption were purchased from the market and processed using sawdust smoke, firewood smoke and charcoal smoke respectively. Some of the fresh fishes were also analyzed as control. The PAHs content were extracted with standard dichloromethane using solid-liquid extraction, and analyzed using Gas chromatography – Mass spectrophotometer (GC-MS) method. The results showed that fish samples processed with sawdust smoke recorded the highest concentrations of total PAHs, having 1.295 mg/kg in Horse markerel and 2.020 mg/kg in Scomber scombrus, followed by firewood smoked samples with total PAHs content of 0.910mg/kg in Horse markrel and 1.175 g/kg in Scomber scombrus while charcoal smoked samples recorded the least total PAHs levels of 0.590 mg/kg in Horse markerel and 0.960 mg/kg in Scomber scombrus. Benzo(a)pyrene concentrations which is usually used to estimate the carcinogenicity of other PAHs was below detection level in both species of fish. PAH4 was proposed by European food safety authority, recommendation level of 30 mg/kg was concluded by the EU regulation. Any PAHs have been associated with intense carcinogenicity in humans, and thus have implication for the quality and safety of these fish products. Therefore, it is imperative that regulatory bodies conduct awareness campaigns to educate the smoked fish processors, traders and consumers on the need to discourage the use of sawdust in smoking fish and adopt safer and improved methods of smoking fishes.

Background: Vernonia amygdalina is a green leafy vegetable that grows in tropical Africa and popularly cultivated in the southern part of Nigeria for its economic, nutritional and ethnomedicine value.Aims: This study analysed the influence of copper-induced abiotic stress on the deoxyribonucleic acid and secondary metabolites of V. amygdalina.Setting: Analyses of plant material were carried out in the Department of Botany, Lagos State University.Methods: Deoxyribonucleic acid (DNA) extraction and Inter Simple Sequence Repeat (ISSR) amplification were performed. Copper (Cu) concentration in leaves and stem of V. amygdalina was determined using inductively coupled plasma-optical emission spectroscopy (ICP-OES), secondary metabolites were determined using gas chromatography–mass spectrometry (GC-MS) and the effect on DNA amplification and profiling was analysed using gel electrophoresis.Results: After 41 days of cultivation, the stem of V. amygdalina significantly bioaccumulated 37 mg/L, 50 mg/L and 215 mg/L of Cu after spiking with 400 mg/L, 1000 mg/L and 2000 mg/L, respectively, whilst the leaves accumulated 52 mg/L, 100 mg/L and 350 mg/L of Cu, respectively. Copper-impregnated soil influenced phytochemicals of the plants by causing inconsistent increase and decrease in specific compounds such as levomenthol, methyl stearate and glycerine. Deoxyribonucleic acid bands of the stem and leaf of V. amygdalina from control site showed no band shift, whilst band shift occurred in the stem and leaf of the Cu-spiked V. amygdalina.Conclusion: This study revealed the leaves of V. amygdalina having higher Cu accumulation capacity than the stems. Also, Cu alters the quality and quantity of phytochemicals in plant parts.

The present study investigated the concentration of heavy metals (lead (Pb), cadmium (Cd), chromium (Cr), copper (Cu), zinc (Zn), and iron (Fe) in water, sediments, Chrysichthys nigrodigitatus and Macrobrachium macrobrachion from Badagry Creek and Ologe Lagoon, between June and November, 2016. Water, sediment, 90 C. nigrodigitatus and 110 M. macrobrachion were collected and digested using standard method. Fe (178.97±15.48mgL -1 ) and Zn (299.63±152.17mgL -1 ) concentrations in water of Ologe Lagoon was higher (p<0.05) than that recorded in Badagry Creek (138.16±39.49 mgL -1, 295.71±9.33 mgL -1 ). Cd concentration in sediment from Badagry Creek (7.96±4.45µgg -1 ) was significantly (p<0.05) higher than that from