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A recent and environmentally more sustainable approach to reducing the levels of pharmaceuticals and their impacts on the environment is to employ green pharmacy which incorporates the principles of green chemistry. These two concepts along with the technique of life-cycle assessment are explained and illustrated with examples of common pharmaceuticals.

The generally very low concentrations of pharmaceutical species in natural environments make both their identification and quantitation very difficult particularly as they often occur as complex mixtures in a background matrix of uncharacterized natural organic matter. This situation has improved significantly with recent developments in analytical techniques involving preconcentration of analytes, their separation from the background matrix, and their sensitive detection and quantitation using mass spectrometric techniques. This chapter will introduce aspects of the sequential steps in the measurement process of sample collection, storage, extraction and preconcentration, separation by high-performance/pressure chromatography, and then detection and quantitation by mass spectrometry. A summary will be given of a range of concentrations of common pharmaceuticals measured in different natural aquatic environments.

A significant proportion of the pharmaceuticals supplied by pharmacies are unused for many reasons and accumulate before ultimately needing disposal. In this chapter, the disposal of pharmaceuticals is discussed, and it is noted that appropriate disposal of pharmaceuticals is not always available; it can be cost prohibitive and selecting the most appropriate method of disposal is not always a simple decision. Take-back programs provide an opportunity for consumers to return unwanted and unused medications and provide a public awareness profile of the magnitude of the problems; however, these can be resource intensive, and again, disposal of the pharmaceuticals collected can incur additional costs

Approaches to lessen the real or potential adverse impact of pharmaceutical residues on the environment can include regional or national legislative controls at each step in their life-cycles beginning with their prescription and subsequent disposal, degradation in wastewater treatment processes, and limits on the their allowed concentrations in effluent discharged into the environment. There is no global agreement on unified legislation to cover all of these control aspects and instead different countries have slowly introduced their own legislation at both the regional and national levels to cover various parts of these control aspects. This situation is illustrated by some of the major legislative acts that have been introduced to control the usage and discharge of pharmaceuticals into the environment in the United States and Canada, the European Union, China, Japan, Australia, and New Zealand. Of particular relevance is the concept of a mixing zone for a receiving environment and how this is currently legislated under the Resource Management Act (RMA) in New Zealand.

The prescription and disposal of pharmaceuticals and their detection in the environment are summarized. The likely environmental impacts and methods to degrade pharmaceuticals in wastewater treatment processes are reviewed along with legislative measures to control their discharge. Suggestions are made for areas of future research in this field.

The majority of the human pharmaceuticals that have been detected in the natural environment have arisen though their discharge in parent or metabolized forms into sewage wastewater which is then treated to various levels of purification to progressively lower the concentrations of pharmaceuticals before discharge of effluent into an aquatic environment. This chapter will introduce a range of physical, biological, and chemical remediation techniques that are the basis of three key wastewater treatment steps—primary, secondary, and tertiary sewage treatment processes. Examples are given of different types of specific processes such as primary sedimentation, secondary biological oxidation, tertiary membrane filtration, and advanced oxidation processes. These are illustrated with the results of both field and laboratory studies of these wastewater treatment processes applied to the degradation and removal of some common pharmaceuticals including paracetamol, diclofenac, ibuprofen, β-blockers, oseltamivir, and fluoxetine. Finally, the effect of the natural organic matrix present in all wastewater on pharmaceutical removal and degradation is briefly considered.

The specific pharmaceuticals that are used globally are governed by access policies (availability, costs, etc.). These policies have a significant impact on the types and volumes of pharmaceuticals that are consumed. These access policies can also make it difficult to quantify the volumes of particular pharmaceuticals that are used. A large body of literature has reported patient behavior that will impact on whether these medications are actually used. Variable adherence rates to medications for a plethora of reasons all contribute to pharmaceuticals that need to be disposed of. An increasing consumer pressure for pharmaceuticals also drives consumption with follow-on consequences for their ultimate disposal.

This review summarizes direct and indirect analytical methods for the detection and quantification of the reactive oxygen species (ROS): 1O2, O2·−/HOO·, H2O2, HO·, and CO3·− in aqueous solution. Each section briefly describes the chemical properties of a specific ROS followed by a table (organized alphabetically by detection method, i.e., absorbance, chemiluminescence, etc.) summarizing the nature of the observable (associated analytical signal) for each method, limit of detection, application notes, and reaction of the probe molecule with the particular ROS.

The Mangatini Stream drains a coal mining area in the mountains of northwestern South Island of New Zealand. Abundant rainfall on pyritic rocks yields acid mine drainage (AMD) to the stream, which flows through a steep gorge at discharges that rapidly increase from 100 m3/s during frequent rain events. The AMD is treated with finely ground limestone, which is discharged as a slurry at a point in the middle of the gorge. The limestone slurry mixes and reacts with the AMD during flow ∼4 km downstream over ∼12 h. Neutralisation reactions increase stream pH from near 3 (untreated Mangatini Stream water impacted by AMD) to 5–6 in the first 250 m downstream, although mixing is commonly incomplete in this zone. Large stream discharge volumes in rain events dilute the neutralising material input, thus driving the pH back towards 4 downstream of treatment. More complete neutralisation is achieved 4 km downstream, even in major rain events, and pH can rise to >7. Partial neutralisation is sufficient to remove most of the dissolved Fe(III) (typically ∼30 mg/L) from the Mangatini Stream in the first 10 m, and remaining dissolved Fe is essentially all Fe(II), which decreases over time as it oxidises and precipitates. Dissolved Al in the Mangatini Stream (typically ∼50 mg/L) decreases steadily downstream over ∼100 m in the limestone mixing zone. Precipitated Fe and Al form amorphous oxyhydroxides that are transported as suspended solids and deposited on the stream bed with excess limestone in zones of low flow velocity. Dissolved Zn is removed from solution by adsorption to Fe oxyhydroxide when pH reaches ∼5, but dissolved Ni remains in solution despite the neutralisation process. Gypsum precipitation occurs throughout the limestone mixing zone, resulting in at least 30% decrease in dissolved SO 4 2 - . Minor ettringite forms in the first 100 m, but then probably redissolves. The limestone dosing system is an effective method of neutralising the effects of AMD and removing most dissolved metals in a steep mountain stream with frequent rain events where this dynamic environment places many constraints on treatment options.

During four seasonally disparate voyages in 2005 and 2006, hydrogen peroxide (H2O2) concentrations were measured in surface seawater east of New Zealand on a transect from 46° 38′ S to 41° 10′ S along the 178° 30′ E meridian. Concentrations of H2O2 along the transect ranged from 8.5 nM to 138.5 nM, and varied seasonally with the highest mean concentrations measured in summer and the lowest in winter. Differences in the intensities of photosynthetically-active radiation between seasons explained much of this seasonal variation in H2O2 concentrations (r2 = 0.997, p Steady-state concentrations of superoxide (HO2 /O2 −) measured in depth-profile samples during a voyage in February 2009 ranged from below the detection limit (218 pM) to a maximum of 32.7 nM. Superoxide maxima were coincident with distinct deep chlorophyll maxima at two sampling sites in the Subtropical Front (STF) east of New Zealand. The data presented in the present study suggest that biologically-mediated production mechanisms can sometimes lead to steady-state concentrations of superoxide in seawater in the nanomolar range. The present study also confirms that solar irradiance alone is capable of explaining much of the natural temporal variation in H2O2 concentrations in surface seawater.

Progress towards development of a river plume ecosystem basis for management of coastal resources requires a thorough understanding of the nature and spatial extent of terrestrial influences on receiving water and seabed characteristics. As a case study, we estimate suspended sediment (SS) loading rates from the Motueka River catchment into Tasman Bay, New Zealand and describe benthic characteristics along a series of transects encompassing the coastal river plume. A mineral-rich geological formation in the headwaters of the river was identified as a storm-generated source of highly elevated concentrations of nickel and chromium in river margin sediments, and coastal sediments extending >5 km offshore. A major storm in 2005, focused in the upper catchment, resulted in an estimated SS discharge of 161,000 tonnes into the Bay. Spatial gradients of a suite of sediment trace metal signatures, organic content and infauna community structure were used to define a river plume depositional footprint of c. 180 km2...

The distribution of trace metals in a ling (Genypterus blacodes) fish fillet was determined from ICP-MS measurements of digests prepared using nitric acid and hydrogen peroxide, followed by microwave digestion. Most trace elements were inhomogeneously distributed in the muscle tissue of the ling with a non-linear increase in concentration towards the tail end of the fillet. This distribution pattern may be connected to the size variation of the individual muscle cells or the change in the ratio of connective tissue to muscle tissue, suggesting that the observed inhomogeneity of muscle elemental distribution may be inherent to all fish species. The concentration of an element in a sample of fish muscle tissue thus depends on the physical location within the fish from which the sample was dissected. Significant differences in trace element concentrations were also detected between the red and white muscle fibres of ling, as well as between the belly flap and the rest of the musculature.

Dissolved organic matter (DOM) was investigated along a gradient across the Subtropical Convergence (STC) off the South Island, New Zealand. Ultrahigh resolution electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS), excitation emission matrix fluorescence (EEM) spectroscopy, and molecular lignin analysis techniques were used to study this DOM. The analysis revealed a group of compounds found only in the coastal DOM samples, which were also characterized by an elevated terrestrial DOM fluorescence pattern and elevated lignin content if compared to the offshore samples. This group exhibited a high degree of carbon unsaturation, as evident from high double bond equivalence minus oxygen values (DBE-O > 9) and maximum fluorescence intensity. Sulfur-containing molecular formulae for summer DOM samples were much more abundant across the entire transect of the STC compared to winter and exhibited distinctly different hydrogen:carbon and oxygen:carbon elemental ratios, suggesting a possible correlation between biological activity and sulfur compounds. The molecular formulae common to all STC samples were compared with those calculated for DOM extracted from freshwater collected from a stream discharging into Doubtful Sound (West Coast, New Zealand). ESI-FT-ICR-MS measurements undertaken in negative electrospray ionization (ESI−) mode indicated that 30% of the molecular formulae were present in both types of DOM, while in positive ESI mode (ESI+) over 90% of the formulae were present in all samples. Hence, a significant portion of the molecular formulae assigned to the solid-phase extractable DOM pool (SPE-DOM) appear to be identical in oceanic and freshwater samples.

Pharmaceuticals have been detected throughout the environment where at least in some cases, they have been shown to have a detrimental effect. Many result from improper patient disposal of unused pharmaceuticals via environmentally-unfriendly routes, such as the sink, toilet or rubbish bin. This review surveys the current peer-reviewed literature on attitudes and practices to medicine disposal methods as reported by patients and the various medication disposal and destruction systems around the world. A literature search was carried out using the keywords 'medicines disposal', 'unused medicines', 'medicines wastage', and 'medication disposal' in the PubMed TM, ISI Web of Knowledge TM, Google Scholar TM, Medline TM, Scopus TM and International Pharmaceuticals Abstracts TM up to the end of May 2010. Twelve peer-reviewed articles with specified sample sizes were selected. The most popular methods for medication disposal were in the garbage, toilet or sink. Liquid medications were more likely to be rinsed down the sink, as opposed to solid tablets and capsules which were more likely deposited in the rubbish bin. Much confusion exists about the 'proper' way of medication disposal as many countries do not have standard medication disposal protocols. Furthermore, some pharmacies around the world refused to accept unused medications or discouraged the practice. Patients with knowledge about the impact of pharmaceuticals in the environment were more likely to return medications for proper disposal and destruction. It is concluded that it is of paramount importance that a formalized protocol for patient disposal and destruction of pharmaceuticals be implemented around the world. Keywords: Medicines disposal, Unused medicines, Medicines wastage, Medication disposal

An equilibrium model based on the CO"2 system was developed to model pH throughout the estuarine salinity range using the composition of the river and seawater end members. In order to validate the model, a spectrophotometric method was used to measure pH in an estuary and laboratory mixing experiments. The model successfully represented the measured pH values (+/-0.1 pH units) for three different river water end member compositions. The pH decreased at low salinities (S ~ 0-2), increased at intermediate salinities (S ~ 2-15), and then stabilised for higher salinity values. Changes in the inorganic carbon speciation in the low salinity region of estuaries result in assimilation of river borne CO"2"("a"q").

The concentrations of selected trace metals were measured in commercially harvested New Zealand scallop species: Chlamys delicatula (queen scallop) from the Otago Coastal Shelf and Pecten novaezelandiae (dredge scallop) collected from 6 sites around the South Island, New Zealand (Titirangi Bay, Collingwood, Milford Sound, Breaksea Sound, Paterson Inlet, and the Chatham Islands). Bivalves were dissected into individual parts, the tissues lyophilized by freeze-drying, and then digested by heating with concentrated HNO3 and H2O2. The resulting solutions were analyzed by inductively coupled atomic emission spectrophotometry to determine the Cd, Cu, Zn, and Fe concentrations. For P. novaezelandiae, the trace metals in whole body tissues were site-specific with mean values ranging from 18–59 µg/g dry weight (dwt) for most sites and high Cd in scallops collected from the Chatham Islands (mean, 332 µg/g dwt). Cu concentrations were low, 6–11 µg/g; average concentrations of Zn ranged from 57–127 µg/g, and...

A comparison is presented of six methods involving nitric acid in conjunction with other reagents to digest three certified marine biological samples (DOLT-3, DORM-3, IAEA-407) and a fish bone homogenate (prepared from Merluccius australis). An inductively coupled plasma-mass spectrometer with an octopole collision cell was used to determine up to 40 elements (Li, B, Na, Mg, Al, K, Ca, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Rb, Sr, Y, Ag, Cd, Cs, Ba, La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, Er, Tm, Yb, Lu, Pb, Th, U) in the digests. These results were assessed in terms of their accuracy and precision, and a flow chart was developed to aid the selection of the optimal digestion method. Although none of the methods was found to give accurate determinations for all elements in the different reference materials, a relatively simple method involving nitric acid and hydrogen peroxide heated in a domestic microwave oven gave the most acceptable results.

Sunlight-induced molecular changes have been observed in two samples of dissolved organic matter (DOM) collected in the Cape Fear River system, North Carolina, USA. The molecular composition of a water sample collected in the Black River (sample B210, salinity 0) and another water sample collected within the Cape Fear River estuary (sample M61, salinity 13.7) were analyzed using an ultrahigh resolution 9.4 Tesla (T) electrospray ionization Fourier transform ion cyclotron resonance mass spectrometer. Additionally, the Ultraviolet/Visible (UV/vis) absorbance as well as the excitation emission matrix (EEM) fluorescence spectra were determined to identify changes in the optical properties associated with photochemical reactions of the chromophoric DOM (CDOM). The molecular formulas forthe Cape Fear River Estuary (M61) sample before the irradiation experiments indicated the presence of highly aromatic compounds which were not present in the unirradiated Black River sample (B210). These aromatic compounds, with oxygen-subtracted double bond equivalents (DBE-O) values greater than nine, are more photoreactive and readily photodegraded relative to saturated compounds. Compounds with DBE-O values below nine are less photoreactive. The UV/vis absorbance and EEM fluorescence results supported this different photodegradation behavior, suggesting that the photoreactivity of CDOM is highly dependent on the molecular composition of the CDOM.

The goal of our research is to better understand the structure and reactivity of natural dissolved organic matter (DOM) in aquatic environments. A more detailed knowledge of these DOM characteristics would lead to a better understanding of carbon cycling in natural waters and processes associated with water treatment using free radical chemistry. Our specific interest in DOM in natural waters is several-fold: 1) the photochemical formation of reactive oxygen species, 2) photobleaching of the DOM in coastal oceans, and 3) using chromophoric DOM (CDOM) as a tracer of water masses and in carbon cycling. Our interest in water treatment is that DOM is the major sink of hydroxyl radicals employed in advanced oxidation processes for the destruction of pollutants and thus adversely affects the efficiency of the process. We are using the techniques of radiation chemistry to explore the fundamental free radical and redox chemistry of DOM. We have initiated a study of the free radical reactions of DOM using isolated fractions of Suwannee River fulvic and humic acids and isolates from various anthropogenic sources. We are also investigating the use of model compounds in an attempt to understand the free radical transients formed from DOM either as a result of free radical reactions or photochemical reactions.

Doubtful Sound, Fiordland National Park, New Zealand has a stable low salinity layer (LSL) at the surface due to the high annual rainfall and an additional freshwater input from the discharge of a hydroelectric power plant. Chromophoric dissolved organic matter (CDOM) distribution dynamics in this LSL were analyzed using Excitation Emission Matrix (EEM) fluorescence and UV/Vis absorption measurements. The levels of CDOM in surface water in Doubtful Sound were much higher than previously reported for coastal zones. CDOM analyzed by UV/Vis absorbance and EEM fluorescence decreased by about 90% within the first 5 m depth. In the first 5 m, the salinity gradient was extreme (5 – 34 salinity), creating a vertical mixing gradient, which appeared to be stable over time. The spectral slope S and the fluorescence index increased during vertical mixing within the first 5 m depth indicating changes in the CDOM chromophores. Observations during a strong rain event revealed that CDOM in a freshwater stream initially increased, but decreased with additional rain (same flow rate), which is an indication that most CDOM was quickly exported within these catchments. Furthermore, the lower CDOM input after substantial rain diluted the surface CDOM level and created a subsurface CDOM maximum. However, shortly after the rain event (

Advanced oxidation/reduction processes (AORPs) are an alternative water treatment that is becoming more widely utilized. Our radiation-chemistry based studies are being used to develop a fundamental understanding of AOP treatment options, and are divided into three complementary types of contaminants; disinfection by-products (DBPs), emerging pollutants of concern (EPoCs), and natural organic matter (NOM). More than 600 DBPs have been identified, and one class that appears to have severe potential adverse health effects is the halonitromethanes (HNMs). Of the nine HNMs, trichloronitromethane (chloropicrin) is the most common, with levels up to 180 nM in US drinking waters. EPoCs are of interest because of their biological activity at low concentrations in water and while the initial focus was on endocrine disruptor chemicals (EDCs) this class has now been expanded to include many other recalcitrant chemicals such as hormones, antibiotics, industrial contaminants, and health care products. Natural organic ...

Estuarine hypoxia (

Chemiluminescence (CL) of acridinium esters (AE) has found widespread use in analytical chemistry. Using the mechanism of the reaction of H2O2 with 10-methyl-9-(p-formylphenyl)acridinium carboxylate trifluoromethanesulfonate and a modified flow injection system, the reaction rates of each step in the mechanism were evaluated and used in a kinetic model to optimize the analysis of H2O2. Operational parameters for a flow injection analysis system (reagent pH, flow rate, sample volume, PMT settings) were optimized using the kinetic model. The system is most sensitive to reaction pH due to competition between AE hydrolysis and CL. The optimized system was used to determine H2O2 concentrations in natural waters, including rain, freshwater, and seawater. The lower limit of detection varied in natural waters, from 352 pM in open ocean seawater (mean, 779 pM +/- 15.0%, RSD) to 58.1 nM in rain (mean, 6,340 nM +/- 0.92%, RSD). The analysis is specific for H2O2 and is therefore of potential interest for atmospheric chemistry applications where organoperoxides have been reported in the presence of H2O2.

Fluoroquinolones, such as enoxacin, are poorly removed by common sewage-treatment processes, leading to their discharge into the environment, where they have unknown, and potentially serious, impacts on plants and aquatic organisms. The aim of the research reported in this paper was to understand the degradation of enoxacin by direct UV (ultraviolet) photolysis and advanced oxidation processes (AOPs) involving UV/H2O2 and photo-Fenton [UV/H2O2/Fe(II)], which may provide an alternative method of removing this compound from water in a treatment plant. Aqueous samples of enoxacin (0.06 mM) were irradiated at 254 nm (Io=2×1016 photon s−1). The presence of H2O2, as well as the addition of FeSO4·7H2O (photo-Fenton process) both resulted in faster degradation kinetics compared to direct irradiation, with all of these systems leading to significant mineralization of enoxacin [>80% removal of total organic carbon (TOC)] within 30 min. The kinetics for the degradation of enoxacin in the presence of natural...

The photoprotective role of mycosporine-like amino acids (MAA) against the generation of DNA cyclobutane pyrimidine dimers (CPD) was studied in the sessile intertidal anemone Actinia tenebrosa and the mobile intertidal gastropod Diloma aethiops through 27 months at a mid-latitude New Zealand location. MAA were sequestered by A. tenebrosa and D. aethiops from their diet, although maximum total MAA levels in both species were not correlated with seasonal variation in maximum ambient UV-B levels recorded at the collection site. Temporal changes in total MAA in A. tenebrosa showed a six months lag-time in their concentration regarding to the environmental UV-B levels. This lag period corresponded to an observed increase in CPD production from spring to summer; suggesting that MAA do not completely protect the anemone from UV-B during summer. For D. aethiops, total MAA concentrations did not change significantly during the study, although qualitative changes in MAA were apparent. A month lag-time in MAA concentration in D. aethiops and possibly the physical barrier that the shell confers to the animal, can explain reduced CPD levels in comparative terms with A. tenebrosa. Although MAA are used by invertebrates for photoprotection, contrasting mobility characteristics and the presence of physical adaptations can confer them important protection levels during temporal changes of UV-B at mid-latitude places of the Southern Hemisphere.

Characterisation of mine waste rock with respect to acid generation potential is a necessary part of routine mine operations, so that environmentally benign waste rock stacks can be constructed for permanent storage. Standard static characterisation techniques, such as acid neutralisation capacity (ANC), maximum potential acidity, and associated acid–base accounting, require laboratory tests that can be difficult to obtain rapidly at remote mine sites. We show that a combination of paste pH and a simple portable carbonate dissolution test, both techniques that can be done in the field in a 15 min time-frame, is useful for distinguishing rocks that are potentially acid-forming from those that are acid-neutralising. Use of these techniques could allow characterisation of mine wastes at the metre scale during mine excavation operations. Our application of these techniques to pyrite-bearing (total S = 1–4 wt%) but variably calcareous coal mine overburden shows that there is a strong correlation between the portable carbonate dissolution technique and laboratory-determined ANC measurements (range of 0–10 wt% calcite equivalent). Paste pH measurements on the same rocks are bimodal, with high-sulphur, low-calcite rocks yielding pH near 3 after 10 min, whereas high-ANC rocks yield paste pH of 7–8. In our coal mine example, the field tests were most effective when used in conjunction with stratigraphy. However, the same field tests have potential for routine use in any mine in which distinction of acid-generating rocks from acid-neutralising rocks is required. Calibration of field-based acid–base accounting characteristics of the rocks with laboratory-based static and/or kinetic tests is still necessary.

Polycyclic aromatic hydrocarbons (PAHs) and heavy metals were measured in road debris collecting in urban areas and in the suspended sediment (SS) component of runoff from two stormwater catchments in Dunedin, New Zealand. Levels in the road debris ranged from 119-527 microg/g for lead, 50-464 microg/g for copper, 241-1 325 microg/g for zinc and 1.20-11.6 microg/g for sigma16PAH. The SS from the largely rural catchment (20% urban) had similar concentrations to the road debris, indicating that this urban material was the main source of the contaminants measured in the stormwater. Similar PAH fingerprint profiles and isomer ratios indicative of dominant pyrogenic (combustion) sources were also found in these two groups of materials. The SS from the 100% urban catchment contained 2- to 6-fold higher concentrations of metals and 10-fold greater levels of sigma16PAH. The higher levels of lead and copper were probably a result of industrial land uses in this catchment, while the additional zinc was linked to an abundance of zinc-galvanised roofing iron in the catchment's residential suburbs. The PAH profiles and isomer ratios were different for this urban catchment and suggested that a disused gasworks was contributing PAHs to the stormwater runoff.

Hydrogen peroxide concentrations are reported for the first time in the surface low salinity layer (LSL) and underlying saline layer (SL) of a fiord. Measurements were made in Deep Cove and Hall Arm in Doubtful Sound, New Zealand under contrasting climatic conditions in early summer (October; wet, windy, and dull: November; dry, still, and sunny). Steady state peroxide concentrations in the range 100–400 nM rapidly declined with depth in the LSL and across the LSL/SL interface. Spectral measurements of absorption coefficients and downwelling irradiance indicated this is largely because of high levels of chromophoric dissolved organic matter (CDOM) in the LSL filtering out the UV component (

A new application of reversed-phase octadecyl (C18) solid phase extraction disks has been developed to separate the colloidally-associated polycyclic aromatic hydrocarbons (PAHs) from those that were truly dissolved in the samples of fresh water. A correction for the retention of small amounts of colloidal material on the C18 disks was required, which would have otherwise lead to minor underestimates in the degree of partitioning between the two phases. Using the humic substance Aldrich Humic Acid (AHA) as a model colloid and the 16 PAHs on the US Enrivonmental Protection Agency priority pollutant list, the partitioning coefficients of the PAHs between the colloidal and truly dissolved phases were shown to be proportional to the hydrophobicity of the PAHs, as measured by their octanol water partition coefficients (Kow). The values for the partition coefficients obtained (cKdoc′) were similar to those previously reported in the literature using alternative methods, confirming that the technique was producing acceptable results. The technique allows the in situ partitioning of PAHs between the truly dissolved and colloidal phases in fresh water bodies to be determined. It will provide an invaluable cross-check of the laboratory-based methods which often require substantial manipulation of the sample and potentially alter the partitioning between the phases.

A water‐balance model was developed for a tidal lake‐wetland complex to: (1) determine the relative contribution of hydrological flows through the lake‐wetland complex; (2) determine the tidal and non‐tidal hydraulic residence times of two lakes in the lake‐wetland complex; and (3) estimate the potential importance of groundwater inputs to the lake‐wetland complex. All surface hydrological inputs to the system were either measured or estimated over 1 year. Daily evaporation from the water bodies was also estimated. Discharge at the outflow of the lake‐wetland complex was monitored to calculate the net daily outflow. A correction procedure was used to remove the error resulting from aliasing of the daily calculation period and the tidal period. The difference between the measured net outflow and that calculated by the water‐balance model indicated that a large amount of net discharge from the lake‐wetland complex may have been a result of previously unrecognised groundwater inputs to the system. T...

Dissolved organic carbon (DOC), formate, acetate, oxalate and a variety of inorganic ions were measured in 54 rain events collected on the southern portion of the South Island of New Zealand. Concentrations of DOC ranged from a low of 10 μM to a high of 401 μM with a volume weighted average concentration of 58 μM which is in the range of concentrations measured at coastal locations in the Northern Hemisphere. The concentration of DOC varied by season with warm season rain (October–March) having somewhat higher concentrations relative to winter rain events (April–September). DOC levels in rain were also influenced by storm origin with maritime events having significantly lower levels relative to terrestrially influenced storms. Formic and acetic acids comprised a relatively small fraction of the DOC pool in New Zealand rain with volume weighted average concentrations of 1.5 μM which was not influenced by storm origin or season. There was a significant correlation between formic and acetic acid concentrations in these rain events suggesting they have similar sources or have different sources of approximately the same strength. This DOC and organic acids data will allow for a better understanding of the global tropospheric transport of carbon compounds and will aid in quantification of atmospheric carbon removal via wet deposition in the Southern Hemisphere.

The trace metal content of roots of samples of the American ginseng natural herbal plant species (Panax quinquefolius) was investigated as a means of differentiating between this species grown on Wisconsin and New Zealand farms, and from Canadian and Chinese sources. ICP-MS measurements were undertaken by ashing samples of the roots and then digestion with conc. HNO3 and H2O2. There was considerable variation in the concentrations of 28 detectable elements along the length of a root, between different roots, between different farms/sources and between different countries. Statistical processing of the log-transformed concentration data was undertaken using principal component analysis (PCA) and discriminant function analysis (DFA). Although PCA showed some differentiation between samples, a much clearer discrimination of the Panax quinquefolius species of ginseng from the four countries was observed using DFA. 88% of the variation between countries could be accounted for by only using discriminant function 1 while 80% of the remaining 12% of the variation between countries is accounted for by discriminant function 2. The Fisher Classification Functions classify 98% of the 87 samples to the correct country of origin with 97% of the cross-validated cases correctly classified. The predictive ability of this DFA model was further tested by constructing 100 discriminant models each using a random selection of the data for two thirds of the 87 sampled ginseng root tops, and then using the resulting classification functions to determine correctly the country of origin of the remaining third of the cases. The mean success rate of the 100 classifications was 92%. These results suggest that measurement and statistical analysis of just the trace metal content of the roots of Panax quinquefolius promises to be an excellent predictor of the country of origin of this ginseng species.

Two methods for the determination of tetrodotoxin(TTX) in marine biota have been developed and validated using ultra-performance LC coupled to triple quadrupole MS. The direct analysis of TTX is completed in one method, while the other method detects the dehydration product of TTX after reaction with base. The methods were validated in a single-laboratory trial and used to test Paphies australis (pipi) samples collected from Whangapoua, New Zealand during April 2011. Pa. australis is a commonly eaten species of bivalve that was found to contain TTX at levels up to 0.80 mg/kg in this study. The methods exhibited recoveries ranging from 94 to 120%, and the within laboratory reproducibility ranged from 6 to 27% for Pleurobranchaea maculata (grey-side gilled sea slug) andbivalve matrixes. Use of the method using a dehydration step showed no evidence of TTX analogs in any ofthe samples.

To assess the relative importance of long- and short-term cellular defense mechanisms in seasonally UV-R-acclimated Actinia tenebrosa (Anthozoa, Actiniidae), individuals were exposed to summer doses of PAR, UV-A, UV-B and enhanced UV-B (20%) for a period of 4 days. Mycosporine-like amino acids (MAAs) and cyclobutane pyrimidine dimer (CPD) concentrations were quantified, while oxidative damage to lipids and proteins, and the activities or levels of the antioxidant enzymes SOD, CAT, GR, GPOX and total glutathione were determined. Our results show that summer UV-R-acclimated individuals had a higher UV-R tolerance, with no significant increases in CPDs levels, than winter-acclimated sea anemones possibly due to higher MAA concentrations. Summer-acclimated individuals showed increased lipid and protein oxidation and GPOX activity only when they were exposed to UV-B at 20% above ambient UV-R levels. In contrast, winter-acclimated sea anemones showed elevated levels of oxidative damage, GPOX and SOD activities after exposure to UV-A or UV-B at ambient and elevated levels. Thus, this study indicates that long-term UV-R acclimation mechanisms such as the accumulation of MAAs could be more important than short-term increases in antioxidant defenses with respect to reducing indirect UV-R damage in intertidal sea anemones.

The influence of a strong surface low‐salinity‐layer (LSL) on the distribution of macro‐nutrients, chlorophyll a, and dissolved oxygen in a fiord was investigated in February and August 1994 in Doubtful Sound, New Zealand. Phosphate and nitrate levels were significantly lower in the LSL than in the underlying saline layer (SL) and increased with depth towards the open ocean suggesting exchange of open ocean water across the deep fiord sill and then vertical mixing with the LSL. Nitrate/phosphate ratios in the range 12.3–16.5 (summer) and 14.9–17.4 (winter) for the LSL compared with 9–10 for the SL for both seasons, may reflect significant differences in phytoplankton species and/or nitrogen cycling between the layers. Elevated silicate levels in the LSL decreasing towards the open ocean were attributed to conservative mixing of the freshwater discharge from the Tail Race with the SL. Biomass (chlorophyll a) in the LSL was quite low even in summer and generally increased towards the open ocean but...

Urban run‐off from a catchment in Dunedin, New Zealand was sampled and chemically characterised (iron (Fe), lead (Pb), copper (Cu), zinc (Zn) in total and 0.4 μm) and their concentrations increased significantly at the beginning of storm run‐off. In contrast, the majority of Cu and Zn was found in the 0.4 μm fraction. The results indicate that Cu and Zn may be more bio‐available, and more difficult to remove by storm‐water treatment, than Pb. The pH level and the concentration of major ions (Ca+2, Na+, Mg+2, K+), dissolved reactive phosphorus, and nitrate generally decreased during storm flows as a result of dilution by r...

The changes in radical concentrations and species brought about by vacuum and gas flow drying of New Vale lignite and Stockton bituminous coal samples were studied. Vacuum drying produces a sudden increase in concentration, flow drying a more gradual but ultimately greater one. For both coals the changes depend on a balance between decarboxylation, which produces new radical sites, and removal of moisture from heteroatomic sites within the coal macrostructure. This balance is influenced by the drying method used. Exposure of dried samples to dry air produces changes in radical concentration consistent with the findings of previous oxidation studies of these coals.

Antidepressant pharmaceuticals have recently been detected at low concentrations in wastewater and surface water. This work reports studies of the direct and indirect photochemical fate and treatment by advanced oxidation of three antidepressant compounds (duloxetine, venlafaxine and bupropion) in solutions of humic acid in order to elucidate their behavior in the natural environment prior to reaching a water treatment facility and potentially entering a potable water supply. Humic acid solution was prepared by adding to distilled water a known amount of organic matter as a photosensitizer. All three antidepressants react very rapidly with hydroxyl radicals ( OH) and hydrated electrons (e − aq ) with rate constants of ∼10 8 to 10 10 M −1 s −1 , but significantly slower with singlet oxygen ( 1 ΔO 2 ) (∼10 3 to 10 5 M −1 s −1 ). The steady-state concentrations of OH and 1 ΔO 2 , in a sample of humic acid solution were measured and used with the second order rate constants to show that the hydroxyl radical was an order of magnitude more effective than the singlet oxygen in the solar-induced photochemical degradation of the antidepressants. Excited state dissolved organic matter also accounted for a substantial portion of degradation of duloxetine, decreasing its half-life by 27% under solar irradiation. Several reaction pathways and by-products arising from the photodegradation were identified using gamma-irradiation followed by LC–MS analysis.

Rainwater samples collected at Karamea on the west coast of the South Island were analysed for pH and ionic composition, An attempt has been made to correlate rainwater samples with air mass origin using air mass back trajectories, Unexpectedly high levels of fluoride (> 1 ppm) were observed in rainwater event samples associated with air mass trajectories from Australia. Mean values for the observed ions were K+ 0.44 ppm, Na+ 4.7 rpm, Ca2+ 2.9 ppm, Mg2+ 0.31 ppm, F- 0.50 ppm, Cl- 12.0 ppm, N03 - 8.2 ppm and SO4 -2 10.1 ppm.

The reductions of a range of anthraquinone sulphonates have been studied by cyclic voltammetry using gold and platinum electrodes. Reductions of the 2-sulphonates in tetraethylammonium hydroxide solutions exhibit two distinct one-electron peaks in the voltammograms in contrast to the single peaks observed from alkali-metal hydroxide solutions. Discrete UV–VIS absorption spectra of the radical anion and quinolate dianion of the 2-sulphonates have been recorded from tetraethylammonium hydroxide solutions using an optically transparent thin-layer electrode (gold minigrid) cell. Studies at different pH values have shown that the most prominent absorption of the 2-sulphonate dianions shows characteristic shifts to shorter wavelengths with each stage of protonation. Observation of the EPR spectra of the radical anion species, electrogenerated in a thin-layer cell, confirms their UV–VIS spectral assignments. The resulting hyperfine splitting constants were assigned to specific proton positions using the additivity principle and the simple Huckel method.

N , N ′-Diethyl- m -toluamide (DEET) is widely used as an insect repellent and has therefore been detected as a contaminant in numerous waste and surface waters. In this study we have determined the absolute reaction rate constants of DEET with the hydroxyl radical and the hydrated electron in aqueous solution as (4.95 ± 0.18) × 10 9 and (1.34 ± 0.04) × 10 9 M −1 s −1 , respectively, using pulse radiation. To provide additional information on the radicals formed upon oxidation, transient spectra were measured from 1 to 150 μs, with transient decay rates determined from the time-dependence of the maximum absorption at 330 nm. These data suggest simple decay of the initially formed radical to stable products. Radical-based destruction mechanisms for destruction of DEET are proposed based on the LC–MS determination of the stable compounds produced by 60 Co γ-irradiation of DEET solutions. These data will be useful in evaluating potential advanced oxidation/reduction processes for the control of DEET and understanding its fate and transport in surface water where analogous radical chemistry is operative.

Many pharmaceutical compounds and metabolites are currently found in surface and ground waters which indicates their ineffective removal by conventional water treatment technologies. Advanced oxidation/reduction processes (AO/ RPs) are alternatives to traditional water treatment, which utilize free radical reactions to directly degrade chemical contaminants. This study reports the absolute rate constants for reaction of three beta-blockers (atenolol, metoprolol, and propranolol) with the two major AO/RP radicals; the hydroxyl radical (*OH) and hydrated electron ((e-)aq). The bimolecular reaction rate constants for *OH are (7.05 +/- 0.27) x 10(9), (8.39 +/- 0.06) x 10(9), and (1.07 +/- 0.02) x 10(10), and for (e-)aq they are (5.91 +/- 0.21) x 10(8), (1.73 +/- 0.03) x 10(8), and (1.26 +/- 0.02) x 10(10), respectively. Transient spectra were observed for the intermediate radicals produced by hydroxyl radical reactions. In addition, preliminary degradation mechanisms and major products were elucidated using 60Co gamma-irradiation and LC-MS. These data are required for both evaluating the potential use of AO/RPs for the destruction of these compounds and for studies of their fate and transport in surface waters where radical chemistry may be important in assessing their lifetime.

This is the first comprehensive study of sources of variation in metal concentrations within the whole tissues of a shallow burrowing, filter-feeding intertidal clam, Austrovenus stutchburyi. Samples were collected from 12 sites in April, August, November and February in 1993-1994 in the vicinity of Otago Harbour and Peninsula, New Zealand. Total tissue trace metal concentrations (microg g(-1) dry weight) were measured in individual animals for the essential metals : Mn, Cu, Zn, Ni and the non-essential Cr using trace-metal clean acid-digestion and ICP-OAES techniques. Average metal concentrations were 3-60 microg g(-1) for Cu, 40-118 microg g(-1) for Zn, 2-12 microg g(-1) for Mn, 5-35 microg g(-1) for Ni and 1-44 microg g(-1) for Cr. These levels decreased with body weight and differed amongst sites except for Cr in February (mid-summer). Highest concentrations occurred at sites close to a city (Dunedin) and within the central harbour region although the Cu, Zn, Ni and Cr concentrations did not correlate with the environmental gradient or season. At one coastal site, samples of both the blue mussel Mytilus galloprovincialis and cockles gave similar trends in trace metal levels. These results suggest that the cockle could be a useful trace metal biomonitor within NZ estuaries.

The tricarboxylic neurotoxin domoic acid (DA) binds trace metals such as iron and copper. In vitro brain slice recording (area CA1 of rat hippocampal slices) was used to assess changes in DA potency in the presence of cadmium and zinc. Cadmium or zinc alone had little or no effect on CA1 responses. DA alone produced hyperexcitability and, with prolonged administration, a robust suppression of CA1 responses. Coadministration of DA with either 2 or 4 μM Cd 2+ produced significant reductions in the potency of DA; less striking effects were seen in the presence of 4 μM Zn 2+ . These findings suggest that interactions of Cd 2+ and Zn 2+ with DA result in the formation of trace metal–neurotoxin complexes which are either unavailable for binding to ionotropic glutamate receptors, or bind without producing full agonist activity.

A study was undertaken to determine whether the isotopic ratios of C and N could be used to uniquely identify municipal solid waste landfill leachate as a source of contamination in the Kaikorai Estuary, Dunedin, New Zealand. Leachate samples were taken from the adjacent Green Island Landfill (GILF), and surface water samples were collected over an 8-month period from the stream and estuary, upstream and downstream of the landfill. Samples were analysed for delta(13)C-dissolved inorganic carbon (DIC), delta(15)N-NO(3)(-), delta(15)N-NH(4)(+), and particulate organic matter (POM) delta(13)C and delta(15)N. Plant material collected along the Kaikorai Stream was analysed for POM delta(13)C and delta(15)N. Leachate was found to have a distinct isotopic signature characterised by a highly enriched delta(13)C-DIC (as much as 16.11+/-0.23 per thousand ) and highly enriched delta(15)N-NH(4)(+) (as much as 27.42+/-0.90 per thousand ). Evidence of leachate contamination was found in the isotopic signatures of downstream delta(13)C-DIC, delta(15)N-NH(4)(+), and delta(13)C and delta(15)N of plant material POM. Other potential sources of enriched delta(13)C-DIC and delta(15)N-NH(4)(+) present in the study area, such as estuarine waters and livestock effluent, were eliminated on the basis of their isotopic characteristics.

INTRODUCTION: One of the recommended methods for households to dispose of unused medications in many countries is to return them to community pharmacies. However, such a practice will only reduce the environmental levels of pharmaceuticals if the medications are also disposed of and destroyed properly by the pharmacies. AIM: This study reports the results of a questionnaire sent to New Zealand community pharmacists regarding disposal practices for unused or expired medications in their workplaces. METHODS: A pre-tested, self-administered questionnaire was sent to 500 randomly selected community pharmacies from all areas of New Zealand. The participants were asked how they disposed of a variety of medications. In addition, participants were also asked about whether they knew how unused medications were destroyed if their pharmacy used a third-party contractor or distributor to dispose of them. RESULTS: Of the 265 respondents, 80.4% and 61.1% respectively reported that solid and semi-solid medications were removed by contractors. However liquid and Class B controlled drugs were predominantly disposed of down the pharmacy sink. Over 60% of the participating pharmacists indicated that they believed the contractors incinerated the collected pharmaceutical waste, and over 90% of the participating pharmacists indicated their wish for a state-run disposal and destruction system. DISCUSSION: Liquid medications and Class B controlled drugs, which were commonly reported to be disposed of down the sewerage system, may increase the potential for environmental pollution by pharmaceuticals in New Zealand. There is a need for increased environmental awareness amongst community pharmacists in New Zealand. KEYWORDS: Medication disposal; pharmaceutical waste; environment; excess medication; community pharmacist

Environmental contextOseltamivir (Tamiflu) is widely used to prevent and treat influenza but conventional wastewater processes involving sedimentation and biotic oxidation do not appear to significantly remove it from sewage, leading to its discharge into the environment. A range of advanced oxidation processes (AOPs) involving photolysis of aqueous solutions of oseltamivir with UV alone, UV/H2O2 and UV/H2O2/FeII is demonstrated to lead to photodegradation of oseltamivir to products with no ecotoxicity observed. These AOPs may therefore offer potentially environmentally friendly sewage water treatment options. AbstractAqueous solutions of the antiviral drug oseltamivir phosphate (OSP, Tamiflu, (3R,4R,5S)-ethyl 4-acetamido-5-amino-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate) were degraded using advanced oxidation processes (AOPs) involving photodegradation with UV alone, UV/H2O2 and UV/H2O2/FeII (photo-Fenton reaction). The photodecay of the parent OSP in all three cases followed first-order kinetics with respective rate constants of 0.21, 1.56 and 1.75 min–1 at 20°C in pH 7 phosphate-buffered Milli-Q water. The rate of UV/H2O2 photolysis in the presence of 2-methylpropan-2-ol was significantly slower with an approximate first-order rate constant of 0.13 min–1 suggesting the involvement of •OH in the degradation process. NMR spectroscopy, mass spectrometry and high-performance liquid chromatography (HPLC) with UV diode array detection were used to identify the crude photoproduct as the hydroxylated OSP derivative (3S,4R,5S)-ethyl 4-acetamido-5-amino-2-hydroxy-3-(pentan-3-yloxy)cyclohexanecarboxylate that occurs by an unknown mechanism. OSP and this crude photoproduct demonstrated no effect on the survival of Quinquelaophonte sp. over 96 h.