Prevalence and risk distribution of schistosomiasis among adults in Madagascar: a cross-sectional study.

BACKGROUND: The goal to eliminate the parasitic disease of poverty schistosomiasis as a public health problem is aligned with the 2030 United Nations agenda for sustainable development goals, including universal health coverage (UHC). Current control strategies focus on school-aged children, systematically neglecting adults. We aimed at providing evidence for the need of shifting the paradigm of schistosomiasis control programs from targeted to generalized approaches as key element for both the elimination of schistosomiasis as a public health problem and the promotion of UHC. METHODS: In a cross-sectional study performed between March 2020 and January 2021 at three primary health care centers in Andina, Tsiroanomandidy and Ankazomborona in Madagascar, we determined prevalence and risk factors for schistosomiasis by a semi-quantitative PCR assay from specimens collected from 1482 adult participants. Univariable and multivariable logistic regression were performed to evaluate odd ratios. RESULTS: The highest prevalence of S. mansoni, S. haematobium and co-infection of both species was 59.5%, 61.3% and 3.3%, in Andina and Ankazomborona respectively. Higher prevalence was observed among males (52.4%) and main contributors to the family income (68.1%). Not working as a farmer and higher age were found to be protective factors for infection. CONCLUSIONS: Our findings provide evidence that adults are a high-risk group for schistosomiasis. Our data suggests that, for ensuring basic health as a human right, current public health strategies for schistosomiasis prevention and control need to be re-addressed towards more context specific, holistic and integrated approaches.

The environmental impacts of palm oil in context.

Delivering the Sustainable Development Goals (SDGs) requires balancing demands on land between agriculture (SDG 2) and biodiversity (SDG 15). The production of vegetable oils and, in particular, palm oil, illustrates these competing demands and trade-offs. Palm oil accounts for ~40% of the current global annual demand for vegetable oil as food, animal feed and fuel (210 Mt), but planted oil palm covers less than 5-5.5% of the total global oil crop area (approximately 425 Mha) due to oil palm's relatively high yields. Recent oil palm expansion in forested regions of Borneo, Sumatra and the Malay Peninsula, where >90% of global palm oil is produced, has led to substantial concern around oil palm's role in deforestation. Oil palm expansion's direct contribution to regional tropical deforestation varies widely, ranging from an estimated 3% in West Africa to 50% in Malaysian Borneo. Oil palm is also implicated in peatland draining and burning in Southeast Asia. Documented negative environmental impacts from such expansion include biodiversity declines, greenhouse gas emissions and air pollution. However, oil palm generally produces more oil per area than other oil crops, is often economically viable in sites unsuitable for most other crops and generates considerable wealth for at least some actors. Global demand for vegetable oils is projected to increase by 46% by 2050. Meeting this demand through additional expansion of oil palm versus other vegetable oil crops will lead to substantial differential effects on biodiversity, food security, climate change, land degradation and livelihoods. Our Review highlights that although substantial gaps remain in our understanding of the relationship between the environmental, socio-cultural and economic impacts of oil palm, and the scope, stringency and effectiveness of initiatives to address these, there has been little research into the impacts and trade-offs of other vegetable oil crops. Greater research attention needs to be given to investigating the impacts of palm oil production compared to alternatives for the trade-offs to be assessed at a global scale.

Household storage, surplus and supra-household storage in prehistoric and protohistoric societies of the Western Mediterranean.

The objective of this paper is to assess foodstuff storage throughout Recent Prehistory (5600-50 BCE) from the standpoint of the three different types (household, surplus and supra-household) identified in the northeast of the Iberian Peninsula. The volumetric data of the underground silos serves as a proxy to evaluate the link between them and the agricultural systems and technological changes. The study also assesses the ability, and specifically, the will of the ancient communities of the northeastern Iberia to generate domestic and extra-domestic surpluses.

Factors shaping local people's perception of ecosystem services in the Atacora Chain of Mountains, a biodiversity hotspot in northern Benin.

BACKGROUND: Atacora Chain of Mountains (ACM) is the Benin part of a range of mountains lying from Benin to Ghana through Togo. It provides goods and services to people and is dominated by rural communities with heavy reliance on natural resources. The ACM may be threatened by the increasing resource needs and the possible shift in people's livelihood priorities brought about by challenges and opportunities ushered in by modernization. This study sought to understand local people's perception of the services derived from the ACM and the socio-demographic factors (age, gender, and level of urbanization of the place people live in) accounting for these perceptions. METHODS: Face to face interviews with 12 focus groups in 3 municipalities were carried out to obtain a list of ecosystem services cited by the participants. At the individual level, 144 people (men, women, young, adult, and old people from either rural or urbanized areas) equally distributed in the 3 municipalities were asked whether they acknowledge each of the services cited by the focus groups. Logistic regressions were then used with generalized linear models (GLM) function in R to analyze the relationships between the probability of acknowledgement of a service by the respondents and their socio-demographic characteristics. RESULTS: Local people perceived the ACM as a provider of provisioning, supporting, and cultural services but cited more provisioning services than the others. The factors considered in this study (gender, location, and age) were all predictors of ecosystem services perception in the ACM. Location influenced people's perception of provisioning and supporting services such that respondents from rural municipalities were more likely to perceive provisioning and supporting services. This is because people in rural areas have a heavier reliance on natural resources. Gender was associated with respondents' perception of supporting, provisioning, and cultural services. Women were more likely to perceive provisioning services and less likely supporting and cultural services. People in each category of gender have a perception of ES linked to their livelihood activities. Young people were less likely to perceive supporting services than adults and old people due to their less involvement in farming activities. CONCLUSIONS: This study showed that gender, location, and age predict local people's perception of ecosystem services in the ACM and livelihood orientation is determinant. The omission of regulation and many of the supporting services questions the future of this mountain chain if its exploitation continues without any awareness and conservation measures.

Enhancing nutrient recycling from excreta to meet crop nutrient needs in Sweden - a spatial analysis.

Increased recycling of nutrient-rich organic waste to meet crop nutrient needs is an essential component of a more sustainable food system. However, agricultural specialization continues to pose a significant challenge to balancing crop nutrient needs and the nutrient supply from animal manure and human excreta locally. For Sweden, this study found that recycling all excreta (in 2007) could meet up to 75% of crop nitrogen and 81% of phosphorus needs, but that this would exceed crop potassium needs by 51%. Recycling excreta within municipalities could meet 63% of crop P nutrient needs, but large regional differences and imbalances need to be corrected to avoid over or under fertilizing. Over 50% of the total nitrogen and phosphorus in excreta is contained in just 40% of municipalities, and those have a surplus of excreta nutrients compared to crop needs. Reallocation of surpluses (nationally optimized for phosphorus) towards deficit municipalities, would cost 192 million USD (for 24 079 km of truck travel). This is 3.7 times more than the total NPK fertilizer value being transported. These results indicate that Sweden could reduce its dependence on synthetic fertilizers through investments in excreta recycling, but this would likely require valuing also other recycling benefits.

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To explore the effects of land use change on the potassium in soil profile under the background of rapid urbanization, we collected data of 187 soil profiles from four typical land use patterns (rice-wheat, rice-vegetable, rice-oil and garden) in Chengdu Plain. The contents of available potassium (AP), slow-acting potassium (SP), mineral potassium (MP), and total potassium (TP) in soil profile under different land use patterns and their relationships were analyzed. Our results showed that compared with the traditional rotation (rice-wheat, rice-oil), soil AP and SP contents significantly varied among different land use patterns. Rice-vegetable rotation increased the contents of AP and SP in the surface soil, while garden land increased the consumption of AP and SP in the soil. For the more stable forms, soil MP and TP, there was no significant difference in their contents under different land use patterns. In the deep soil, the content of AP in the rice-vegetable rotation pattern was significantly decreased with deepening soil layer, and the AP in traditional rotation was significantly higher than that in garden land. The trend of SP was opposite to that of AP. The difference of MP and TP in different land use patterns was small. Among the four land use patterns, the ratio of AP to TP and SP to TP in the lower layer of rice-vegetable rotation was higher than that in other patterns, while the ratio of AP to TP decreased significantly under different land use patterns at 20-40 cm. The change of SP to TP with the downward ratio of soil layer was opposite to that of AP to TP. Additionally, the ratio of MP to TP was relatively stable under different land use patterns. Therefore, different land use patterns exerted significant effects on the distribution of AP and SP in the soil profile of Chengdu Plain.

Sustainable palm oil may not be so sustainable.

The globalization of the palm oil trade poses a menace to the ecosystem integrity of Southeast Asia. In this short communication, we briefly discuss why palm oil certifications may have failed as an effective means to halt forest degradation and biodiversity loss. From a comparison of multiple new datasets, we analysed recent tree loss in Indonesia, Malaysia, and Papua New Guinea, and discovered that, from 2001 to 2016, about 40% of the area located in certified concessions suffered from habitat degradation, deforestation, fires, or other tree damages. Certified concessions have been subject to more tree removals than non-certified ones. We also detect significant tree loss before and after the start of certification schemes. Beyond non-governmental organisations' concern that Roundtable on Sustainable Palm Oil (RSPO) and Palm Oil Innovation Group (POIG) certifications allow ongoing clearance of any forest not identified as of high conservation values (HCV) or high carbon stock (HCS), we suggest an alarming and previously overlooked situation, such as that current "sustainable palm oil" is often associated with recent habitat degradation and forest loss. In other words, certified palm oil production may not be so sustainable.

Comparative on plant stoichiometry response to agricultural non-point source pollution in different types of ecological ditches.

Long-term agricultural development has led to agricultural non-point source (NPS) pollution. Ecological ditches (eco-ditch), as specific wetland systems, can be used to manage agricultural NPS water and achieve both ecological and environmental benefits. In order to understand which type of eco-ditch systems (Es, soil eco-ditch; Ec, concrete eco-ditch; Eh, concrete eco-ditch with holes on double-sided wall) is more suitable for plant nutrient balance meanwhile reducing NPS water (total nitrogen [TN], about 10 mg/L; total phosphorus [TP], about 1 mg/L), it is essential to evaluate the plant (Vallisneria natans) stoichiometry response to water in different types of eco-ditches under static experiment. The results indicated that there were no significant differences in TP removal efficiency among three eco-ditches, yet Eh systems had the best TN removal efficiency during the earlier experimental time. Addition of agricultural NPS water had varying effects on plants living in different types of eco-ditch systems. Plant organ stoichiometry of V. natans varied in relation to eco-ditch types. Plant stoichiometry (C:N, C:P, and N:P) of V. natans in Eh systems could maintain the homeostasis of nutrients and was not greatly affected by external changing environment. V. natans in Es systems can more easily modify the nutrient contents of organs with regard to nutrient availability in the environment. Our findings provide useful plant stoichiometry information for ecologists studying other specific ecosystems.

Modeling Water and Nutrient Movement in Sandy Soils Using HYDRUS-2D.

Models help to describe and predict complex processes and scenarios that are difficult to understand or measure in environmental management systems. Thus, model simulations were performed (i) to calibrate HYDRUS-2D for water and solute movement as a possible decision support system for Candler and Immokalee fine sand using data from microsprinkler and drip irrigation methods, (ii) to validate the performance of HYDRUS-2D using field data of microsprinkler and drip irrigation methods, and (iii) to investigate Br, NO, and water movement using annual or seasonal weather data and variable fertigation scenarios. The model showed reasonably good agreement between measured and simulated values for soil water content ( = 0.87-1.00), Br ( = 0.63-0.96), NO-N ( = 0.66-0.98), P ( = 0.25-0.78), and K ( = 0.44-0.99) movement. The model could be successfully used for scheduling irrigation and predicting nutrient leaching for both microsprinkler and drip irrigation systems on Florida's sandy soils.

Stream Nitrogen, Phosphorus, and Sediment Concentrations Show Contrasting Long-term Trends Associated with Agricultural Change.

Stream water quality can be greatly influenced by changes in agricultural practices, but studies of long-term dynamics are scarce. Here we describe trends over 21 yr (1994-2014) in nutrients and suspended sediments in three streams in a Midwestern US agricultural watershed. During this time, the watershed experienced substantial changes in agricultural practices, most importantly a pronounced shift from conventional to conservation tillage. In the 1990s and early 2000s, NH, soluble reactive P, and suspended sediment concentrations (standardized for discharge and season) each declined significantly (>4-12% per year) in at least two of the three streams ( < 0.01), whereas NO changed relatively little. However, since the early 2000s, declines in NH and sediment concentrations have slowed, soluble reactive P concentrations have not declined and may actually have increased, and NO concentrations have declined sharply. The more recent lack of decline in soluble reactive P coincides with a plateau in the prevalence of conservation tillage and may be because of increased soil P stratification due to long-term reduced tillage. The more recent decline in NO may be due to improved efficiency of N fertilizer use, increased soil denitrification, and/or declines in atmospheric N deposition. Our study shows that stream concentrations of N, P, and sediment can respond in contrasting ways to changes in agriculture, and that temporal trends can moderate, accelerate, or reverse over decadal timescales. Management strategies must consider contrasting temporal responses of water quality indicators and may need to be adaptively adjusted at scales of years to decades.

Spreading Waves in a Farmers and Hunter-Gatherers Model of the Neolithic Transition in Europe.

The Neolithic transition began the spread of early agriculture throughout Europe through interactions between farmers and hunter-gatherers about 10,000 years ago. Archeological evidence produced by radiocarbon dating indicates that the expanding velocity of farming is roughly constant all over Europe. Theoretical understanding of such evidence has been performed from mathematical modeling viewpoint. However, the expanding velocity determined by existing modeling approaches is faster than the observed velocity. For understanding this difference, we propose a three-component reaction-diffusion system which consists of two different types of farmers (sedentary and migratory) and hunter-gatherers from the viewpoint of the influence of farming technology. Our purpose is to study the relation between the expanding velocity of farmers and the farming technology parameter (say, [Formula: see text]). In this paper, we mainly focus on the one-dimensional traveling wave solution with minimal velocity and show that the minimal velocity decreases, as [Formula: see text] increases. This can be compatible with the observed velocity when farming technology is developed. Our results suggest that the reason for the slowdown of the Neolithic transition might be related to the increase in the development of farming technology.

An approach to identify the spatiotemporal patterns of nitrogen flows in food production and consumption systems within watersheds.

Human has greatly disturbed nitrogen (N) cycles through the food production and consumption (FPC) activities, which caused serious environmental consequences. A few studies address the pathways of N cycles to clarify the interrelationships between human activities and the altered N cycles, especially in terms of the spatial aspects of N flows, which are also influenced by natural factors. Here, we developed an integrated model to quantify the spatiotemporal patterns of N flows within the FPC and applied it to the Chaohu Watershed from 1949 to 2012. We found that total N inputs into the FPC increased by 6-fold during 1949-2012, while N inputs from chemical fertilizer had the largest increase, with an annual growth rate of 8.6%. N generation in manure doubled, but the recycling rate decreased by 50% in the study period. The total N losses increased from 17 to 130Gg-N/yr between 1949 and 2012. Annually, ~7% of total N losses was discharged into surface water annually, which peaked at 9.5Gg-N/yr during 1998-2003, two times as that in the early 1980s when algae blooms first occurred in Chaohu lake. Spatially, around one-fifth of the catchment area was responsible for all of N losses to surface water. These intensive areas located in the eastern and southern-central regions, which were identified as the critical areas for priority N mitigation. This study provided a method to depict spatiotemporal patterns of regional N flows for identifying the critical sources and areas of N pollution for precision watershed management.

Do Coffee Farmers Benefit in Food Security from Participating in Coffee Cooperatives? Evidence from Southwest Ethiopia Coffee Cooperatives.

BACKGROUND: Most coffee in Ethiopia is produced by smallholder farmers who face a daily struggle to get sufficient income but also to feed their families. At the same time, many smallholder coffee producers are members of cooperatives. Yet, literature has paid little attention to the effect of cooperatives on combating food insecurity among cash crop producers including coffee farmers. OBJECTIVE: The objective of the study was to investigate how coffee cooperative membership may affect food security among coffee farm households in Southwest Ethiopia. METHODS: The study used cross-sectional household data on income, expenditure on food, staple food production (maize and teff), and utilization of improved inputs (fertilizer and improved seed) collected from 256 randomly selected farm households (132 cooperative members and 124 nonmembers) and applied an inverse probability weighting (IPW) estimation to assess the impact of cooperative membership on food security. RESULTS: The result revealed that cooperative membership has a positive and significant effect on staple food production (maize and teff) and facilitated technological transformation via increased utilization of fertilizer and improved seeds. Nonetheless, the effect on food expenditure and income could not be confirmed. CONCLUSION: Findings suggest a trade-off between coffee marketing and input supply functions of the cooperatives, impairing their true food security impact from the pooled income and production effect.

Detecting seasonal and cyclical trends in agricultural runoff water quality-hypothesis tests and block bootstrap power analysis.

Seasonal and cyclic trends in nutrient concentrations at four agricultural drainage ditches were assessed using a dataset generated from a multivariate, multiscale, multiyear water quality monitoring effort in the agriculturally dominant Lower Rio Grande Valley (LRGV) River Watershed in South Texas. An innovative bootstrap sampling-based power analysis procedure was developed to evaluate the ability of Mann-Whitney and Noether tests to discern trends and to guide future monitoring efforts. The Mann-Whitney U test was able to detect significant changes between summer and winter nutrient concentrations at sites with lower depths and unimpeded flows. Pollutant dilution, non-agricultural loadings, and in-channel flow structures (weirs) masked the effects of seasonality. The detection of cyclical trends using the Noether test was highest in the presence of vegetation mainly for total phosphorus and oxidized nitrogen (nitrite + nitrate) compared to dissolved phosphorus and reduced nitrogen (total Kjeldahl nitrogen-TKN). Prospective power analysis indicated that while increased monitoring can lead to higher statistical power, the effect size (i.e., the total number of trend sequences within a time-series) had a greater influence on the Noether test. Both Mann-Whitney and Noether tests provide complementary information on seasonal and cyclic behavior of pollutant concentrations and are affected by different processes. The results from these statistical tests when evaluated in the context of flow, vegetation, and in-channel hydraulic alterations can help guide future data collection and monitoring efforts. The study highlights the need for long-term monitoring of agricultural drainage ditches to properly discern seasonal and cyclical trends.

Groundwater nutrient inputs into an urbanized tropical estuary system in Indonesia.

Groundwater discharge is known to transport nutrients into estuaries at several locations around the world. However, few studies report groundwater-associated nutrient fluxes from tropical developing regions such as Southeast Asia, even though this area shows the strongest human modifications in the coastal zone worldwide. We investigated groundwater nutrient flux into two streams and estuaries (Awur and Sekumbu Bay) in the urban area of Jepara, Indonesia, and its relation with the land usage surrounding the estuaries. We found that average concentrations of NO3, NH4, and PO4 in Jepara's aquifer reached 145µM, 68µM, and 14µM, respectively, and our results indicate that these were mainly originated from untreated sewage, agriculture, and manure input. Approximately 2200tonNyear-1 and 380tonPyear-1 were removed in the soil and aquifer before the nutrients were discharged into the river. The total groundwater discharge into the river and estuary was estimated to 461×103m3d-1, or up to 42% of the river discharge. Discharge of groundwater-associated NO3 (72×103mold-1), NH4 (34×103mold-1), PO4 (5×103mold-1), and additional surface runoff may contribute to eutrophication and a decrease of nearshore surface water quality. Nutrient concentrations in groundwater, river, and coastal seawater in the Jepara region are similar to those found in major urban areas in Southeast Asia, e.g. Manila and Bangkok, even though Jepara has smaller size and population. Thus, our results indicate that medium populated cities with highly modified regional land use can contribute a significant amount of nutrient discharge in the coastal area and should be included in global assessments of nutrient budget calculation.

Quantifying trade-offs between future yield levels, food availability and forest and woodland conservation in Benin.

Meeting the dual objectives of food security and ecosystem protection is a major challenge in sub-Saharan Africa (SSA). To this end agricultural intensification is considered desirable, yet, there remain uncertainties regarding the impact of climate change on opportunities for agricultural intensification and the adequacy of intensification options given the rapid population growth. We quantify trade-offs between levels of yield gap closure, food availability and forest and woodland conservation under different scenarios. Each scenario is made up of a combination of variants of four parameters i.e. (1) climate change based on Representative Concentration Pathways (RCPs); (2) population growth based on Shared Socioeconomic Pathways (SSPs); (3) cropland expansion with varying degrees of deforestation; and (4) different degrees of yield gap closure. We carry out these analyses for three major food crops, i.e. maize, cassava and yam, in Benin. Our analyses show that in most of the scenarios, the required levels of yield gap closures required to maintain the current levels of food availability can be achieved by 2050 by maintaining the average rate of yield increases recorded over the past two and half decades in addition to the current cropping intensity. However, yields will have to increase at a faster rate than has been recorded over the past two and half decades in order to achieve the required levels of yield gap closures by 2100. Our analyses also show that without the stated levels of yield gap closure, the areas under maize, cassava and yam cultivation will have to increase by 95%, 102% and 250% respectively in order to maintain the current levels of per capita food availability. Our study shows that food security outcomes and forest and woodland conservation goals in Benin and likely the larger SSA region are inextricably linked together and require holistic management strategies that considers trade-offs and co-benefits.

Linking carbon stock change from land-use change to consumption of agricultural products: A review with Indonesian palm oil as a case study.

Numerous analyses have been performed to quantitatively link carbon stock change caused by land-use change (CSC-LUC) to consumption of agricultural products, but results differ significantly, even for studies focussing on the same region or product. This is due to the different focuses and interpretations of the links between direct drivers and underlying causes of CSC-LUC, which can be translated into differences in key functions, i.e. specific methods, algorithms and parameters embedded in the analysis. Using the example of Indonesian palm oil production (often associated with CSC-LUC), this paper carries out a meta-analysis of 12 existing studies, determines the different settings for the key functions embedded in consumption-based CSC-LUC studies and discussed their implications for policymaking. It identifies the underlying reasons of adopting different settings within the eight key functions and their advantages and trade-offs. Examples are the way of determining how deforestation is linked to oil palm, and the inclusion of non-agriculture and non-productive drivers in the accounting to weight their roles in CSC-LUC in comparison to palm oil consumption. Following that, the quantitative results from the selected studies were processed and harmonised in terms of unit, allocation mechanism, allocation key and amortisation period. This resulting in ranges of 0.1-3.8 and -0.1-15.7 tCO2/t crude palm oil for historical and projection studies, respectively. It was observed that CSC-LUC allocated to palm oil is typically lower when propagating effects and non-agricultural or non-productive drivers were accounted for. Values also greatly differ when marginal and average allocation mechanisms were employed. Conclusively, individual analyses only answer part of the question about CSC-LUC drivers and have their own strengths and weaknesses. Since the context can be very different, using quantitative results from a single study for accounting purposes in policymaking is not recommended. Instead, insights from different studies should be combined, e.g. the relative role of logging and oil palm or the contribution to CSC-LUC in regional and global perspectives.

Magnitude of anthropogenic phosphorus storage in the agricultural production and the waste management systems at the regional and country scales.

Based on a systematic review of 17 recent substance flow analyses of phosphorus (P) at the regional and country scales, this study presents an assessment of the magnitude of anthropogenic P storage in the agricultural production and the waste management systems to identify the potential for minimizing unnecessary P storage to reduce the input of P as mineral fertilizer and the loss of P. The assessment indicates that in case of all (6) P flow analyses at the regional scale, the combined mass of annual P storage in the agricultural production and the waste management systems is greater than 50 % of the mass of annual P inflow as mineral fertilizer in the agricultural production system, while this is close to or more than 100 % in case of half of these analyses. At the country scale, in case of the majority (7 out of 11) of analyses, the combined mass of annual P storage in the agricultural production and the waste management systems has been found to be roughly equivalent or greater than 100 % of the mass of annual P inflow as mineral fertilizer in the agricultural production system, while it ranged from 30 to 60 % in the remaining analyses. A simple scenario analysis has revealed that the annual storage of P in this manner over 100 years could result in the accumulation of a massive amount of P in the agricultural production and the waste management systems at both the regional and country scales. This study suggests that sustainable P management initiatives at the regional and country scales should put more emphasis on minimizing unwanted P storage in the agricultural production and the waste management systems.

Reduced persistence of the macrolide antibiotics erythromycin, clarithromycin and azithromycin in agricultural soil following several years of exposure in the field.

The macrolide antibiotics erythromycin, clarithromycin and azithromycin are very important in human and animal medicine, and can be entrained onto agricultural ground through application of sewage sludge or manures. In the present study, a series of replicated field plots were left untreated or received up to five annual spring applications of a mixture of three drugs to achieve a nominal concentration for each of 10 or 0.1mgkg(-1) soil; the latter an environmentally relevant concentration. Soil samples were incubated in the laboratory, and supplemented with antibiotics to establish the dissipation kinetics of erythromycin and clarithromycin using radioisotope methods, and azithromycin using HPLC-MS/MS. All three drugs were dissipated significantly more rapidly in soils with a history of field exposure to 10mgkg(-1) macrolides, and erythromycin and clarithromycin were also degraded more rapidly in field soil exposed to 0.1mgkg(-1) macrolides. Rapid mineralization of (14)C-labelled erythromycin and clarithromycin are consistent with biodegradation. Analysis of field soils revealed no carryover of parent compound from year to year. Azithromycin transformation products were detected consistent with removal of the desosamine and cladinose moieties. Overall, these results have revealed that following several years of exposure to macrolide antibiotics these are amenable to accelerated degradation. The potential accelerated degradation of these drugs in soils amended with manure and sewage sludge should be investigated as this phenomenon would attenuate environmental exposure and selection pressure for clinically relevant resistance.