Arnljot Einride Strømseng

Speciation of lead, copper, zinc and antimony in water draining a shooting range—Time dependant metal accumulation and biomarker responses in brown trout (Salmo trutta L.)

The speciation of Pb, Cu, Zn and Sb in a shooting range run-off stream were studied during a period of 23 days. In addition, metal accumulation in gills and liver, red blood cell ALA-D activity, hepatic metallothionine (Cd/Zn-MT) and oxidative stress index (GSSG/ tGSH levels) in brown trout (Salmo trutta L.) exposed to the stream were investigated. Fish, contained in cages, were exposed and sampled after 0, 2, 4, 7, 9, 11 and 23 days of exposure. Trace metals in the water were fractionated in situ according to size (nominal molecular mass) and charge properties. During the experimental period an episode with higher runoff occurred resulting in increased levels of metals in the stream. Pb and Cu were mainly found as high molecular mass species, while Zn and Sb were mostly present as low molecular mass species. Pb, Cu and Sb accumulated on gills, in addition to Al origination from natural sources in the catchment. Pb, Cu and Sb were also detected at elevated concentration in the liver. Blood glucose and plasma Na and Cl levels were significantly altered during the exposure period, and are attributed to elevated concentrations of Pb, Cu and Al. A significant suppression of ALA-D was detected after 11 days. Significant differences were detected in Cd/Zn-MT and oxidative stress (tGSH/GSSG) responses at Day 4. For Pb the results show a clear link between the HMM (high molecular mass) positively charged Pb species, followed by accumulation on gills and liver and a suppression in ALA-D. Thus, high flow episodes can remobilise metals from the catchment, inducing stress to aquatic organisms.

Episodic discharge of lead, copper and antimony from a Norwegian small arm shooting range

Small arm shooting ranges are major deposits of lead (Pb), copper (Cu), antimony (Sb), and zinc (Zn) from use of ammunition. Metals and metalloids from the ammunition residues may leach into the soil and surrounding watercourses and may pose a threat to exposed wildlife and humans. Discharge of elements is dependent on several factors such as soil properties, hydrological conditions, precipitation and time. In order to identify strategies to limit spread of ammunition residues from shooting ranges it is of importance to gain knowledge of the mobility of the elements from the spent bullets. Here we have monitored the levels of Pb, Cu and Sb in a small drainage stream from a Norwegian military small arm shooting range in 2001 and 2006. The first campaign in 2001 was initiated ahead of the snow-melting period in the spring and continued two months in order to quantify discharge and discharge patterns of the selected elements in the drainage stream. Two shorter campaigns were performed in autumn 2001 during an excavation, and in summer 2006. Mean levels of Pb, Cu and Sb in the stream during the first monitoring period in 2001 were 14 microg/l, 39 microg/l and 9 microg/l respectively. High flow, following precipitation, led to an approximately fourfold increase in the concentration of Pb and threefold increase in the level of Cu and Sb compared to low discharge concentrations. An estimation of discharge of the metals showed that the snow melting period and precipitation events constituted to a large proportion of the total release. A sudden increase in the levels can induce more stress and reduce survival of exposed aquatic animals due to the short time available for adaptation.

Short-term temporal variations in speciation of Pb, Cu, Zn and Sb in a shooting range runoff stream.

This study was designed to explore the changes in physico-chemical forms of Pb, Cu, Zn and Sb in a stream draining a contaminated shooting range, located at Steinsjøen in the South-Eastern part of Norway, during a period of 21days. To obtain information on the element species distribution, an interphased size and charge fractionation system was applied, where membrane filtration (0.45microm) and ultrafiltration using hollow fibre (nominal cut off 10kDa) were performed prior to charge fractionation using chromatography (cationic and anionic exchange resins). The results show that Pb mainly was present as particulate and colloidal high molecular mass (HMM) species, Cu as colloidal (HMM) and low molecular mass (LMM) species, while Sb and Zn were mainly present as LMM species. The total element concentrations of Pb, Cu, Zn and Sb were positively correlated to water flow and dissolved organic carbon (DOC), suggesting these are important factors in controlling the run-off of the investigated elements in this catchment. During episodes of higher water flow, the increase in element concentration was mainly in the colloidal fraction. Partial redundancy analysis (pRDA) revealed that variations in pH, HMM organic carbon (HMM OC) and LMM organic carbon (LMM OC) explained 47% of the variation in size distribution of the elements, while variations in precipitation and water flow explained 48% of the variation in the charge distribution of the elements. The variation in concentrations during the period varied by a factor of 4, also stressing the importance of frequent sampling opposed to spot sampling in environmental surveys and risk assessments.

Use of sorbents for purification of lead, copper and antimony in runoff water from small arms shooting ranges

Different sorbents were tested in situ for their ability to reduce the concentration of Cu, Sb and Pb in drainage water from a shooting range. The sorbents tested were: Brimac(®) charcoal, olivine mixed with elemental iron powder, magnetite and Kemira(®) iron hydroxide. The mean sorption of Cu, Sb and Pb was 84%, 66%, 85% with Brimac(®) charcoal and 58%, 78% and 69% with Kemira(®) iron hydroxide. Good sorption of Cu and Pb was achieved using olivine with 5% elemental Fe powder, which resulted in a sorption of 81% and 87%, respectively. The Fe-olivine filters were less efficient in reducing the concentration of Sb, but increasing the Fe content improved Sb sorption. In periods with high concentrations of Pb, Cu and Sb in the creek, such as during precipitation, the sorbent efficacy improved. This might be due to changes in the physico-chemical form of the metals, or to a higher fraction of elements being physically retained in the form of particles or colloids.

Selective adsorption of lead, copper and antimony in runoff water from a small arms shooting range with a combination of charcoal and iron hydroxide.

Metals and metalloids from ammunition residues at small arms shooting ranges leach into the soil and surrounding watercourses and may pose a threat to exposed wildlife and humans. To reduce the potential impact of heavy metal on the environment a field study was performed with different sorbents in order to reduce the metal concentration in polluted water from a shooting range. Two sorbents were tested in situ for their ability to reduce the concentration of Cu, Sb and Pb: Brimac(®) charcoal and Kemira(®) iron hydroxide. The mean sorption of Cu, Sb and Pb was 85%, 65%, and 88% respectively when using the charcoal and 60%, 85% and 92% respectively with the iron hydroxide. Even better sorption of the elements was achieved when the two sorbents were combined in order to increase their selectivity. The best results were achieved in the filter in which the water percolated the charcoal first and the iron hydroxide last, with a mean sorption of Cu, Sb and Pb of 89%, 90% and 93% respectively. This preparation gave a significant better sorption of Cu compared to the filter in which the water percolated the iron hydroxide first and the charcoal last. The different effect between the two filters may be due to pH, since charcoal has alkaline properties and iron hydroxide has acidic properties. For large scale experiments or in filter devices we therefore recommend use of a combination of different reactive sorbents.

Application of sorbents in different soil types from small arms shooting ranges for immobilization of lead (Pb), copper (Cu), zinc (Zn), and antimony (Sb)

PurposeSoil contamination of ammunition residues at shooting ranges for small arms may be followed by leaching of lead (Pb), copper (Cu), zinc (Zn), and antimony (Sb). Mixing stabilizing agents into the soil may reduce the mobility of the contaminants. To avoid risk of unexpected effects of a stabilizing agent in large-scale measures, the effect of an amendment should be tested on a small scale in advance. Two different amendments, ferric oxyhydroxide powder (CFH-12 from a commercial provider) and zerovalent iron (powder or grit), were mixed into different soil types in order to test their generic effects as stabilizing agents in contaminated soil from shooting ranges. Factors that were considered for their effects were soil water pH, limestone addition, soil chemical composition, and content of organic matter.Materials and methodsThe stabilizing agents (2–4% weight basis) were mixed into four different soil types contaminated with ammunition residues. The effects of the amendments were elucidated in two column experiments, one small-scale and one larger-scale experiment. Leaching of Pb, Cu, Zn, and Sb from the soil mixed with stabilizing agents was compared with reference soil with no amendments added.Results and discussionBest performance was achieved on leaching of Sb irrespective of the type of iron amendment and soil type. The Sb concentrations in the soil leachates were 55–94% less than in the leachates from the reference soils. Both amendments mixed into an acidic soil reduced the Pb, Cu, and Zn concentrations in the soil leachates in the range of 79–99%. The ability of the amendment to reduce leaching of Pb, Cu, and Zn from the other soil types was highly dependent on soil pH. CFH-12 was acidic and pH had to be balanced with limestone. The general trend was that the iron amendments reduced leaching of the elements in the order Sb>>Cu > Pb ≥ Zn.ConclusionsIron amendment may be suitable as stabilizing agents for Pb, Cu, Zn, and Sb in soil. The soil pH appeared to be the most important factor governing the mobility of the ammunition residues in the soils. Overall, best effect was achieved with zerovalent iron, which can be purchased at low cost and appeared to have minor influence on the properties of the soils.