Microplastics in Sewage Sludge: Effects of Treatment

Waste water treatment plants (WWTPs) are receptors for the cumulative loading of microplastics (MPs) derived from industry, landfill, domestic wastewater and stormwater. The partitioning of MPs through the settlement processes of wastewater treatment results in the majority becoming entrained in the sewage sludge. This study characterized MPs in sludge samples from seven WWTPs in Ireland which use anaerobic digestion (AD), thermal drying (TD), or lime stabilization (LS) treatment processes. Abundances ranged from 4196 to 15 385 particles kg^-1 (dry weight). Results of a general linear mixed model (GLMM) showed significantly higher abundances of MPs in smaller size classes in the LS samples, suggesting that the treatment process of LS shears MP particles. In contrast, lower abundances of MPs found in the AD samples suggests that this process may reduce MP abundances. Surface morphologies examined using scanning electron microscopy (SEM) showed characteristics of melting and blistering of TD MPs and shredding and flaking of LS MPs. This study highlights the potential for sewage sludge treatment processes to affect the risk of MP pollution prior to land spreading and may have implications for legislation governing the application of biosolids to agricultural land.

Lacking the 'protective label' of diabetes: Phenytoin-induced distal symmetrical peripheral neuropathy. A clinical case report

This report documents an unusual case of distal symmetrical peripheral neuropathy (DSPN) in an otherwise healthy patient without diabetes mellitus (DM) presenting to a podiatric wound care clinic. The development of gas gangrene coupled with Charcot neuroarthropathic changes ultimately resulted in a potentially life-saving transmetatarsal (TMT) amputation. Causation of, or at least a contributor to, the DSPN was likely phenytoin usage for epileptic seizures. Long-term use of phenytoin can lead to axonal shrinkage and random clusters of nerve demyelination [1]. Clinical standards for DM-induced DSPN indicate that annual comprehensive neurological assessment to detect nerve function deterioration is warranted [2]. This can aid in identifying patients at high risk of diabetic foot ulceration. However, oftentimes, patients exhibiting medication-induced neuropathy are not assessed to determine severity of the neuropathy nor are they educated about ulcer prevention in the same manner as patients with DM. This report advocates for a standardized threshold of diagnostic and preventative investigation for neuropathy of all aetiologies; diabetic, traumatic, viral, medication-induced and idiopathic.

Characterization of patients with diabetic foot disease presenting to an Irish Podiatry Centre: profiling suitability for entry to a clinical trial of advanced wound therapeutics

BACKGROUND

Diabetes mellitus, coined the 'Black Death of the Twenty-First Century', is associated with complications, including foot ulceration with potential loss of limb. There is a need for development of new wound therapies through completion of robust clinical trials.

AIMS

To profile demographics and wound characteristics of an Irish cohort with diabetes, forecast eligibility for entry to a clinical trial of advanced wound therapeutics, and adjust criteria to optimize eligibility for enrolment.

METHODS

A cross-sectional study of out-patients attending a Podiatry centre over 12 weeks was conducted. Information was collected through clinical assessment, including Neuropathy Disability Score and Ankle-Brachial Pressure Index. Ulcers were characterised as 'healing' or 'non-healing'; a 'healing' wound decreased by 30 % over the previous month, accomplished by retrospective analysis of files. Statistics, including binomial logistic regression and column analysis for eligibility assessment, were conducted.

RESULTS

Seventy-four participants were identified with a mean age of 67 (± 8.79) years. Non-healing DFU status correlated significantly with larger wound area (P = 0.013), infection (P = 0.009), and greater degrees of ischaemia (P = 0.015). The eligibility criteria were modelled after those proposed by the EU consortium project REDDSTAR. In this Irish population, these criteria limit eligibility to 1.4 %.

CONCLUSIONS

This research found an eligibility criterion of wound area 2-10 cm² for enrolment in a clinical trial of mesenchymal stromal cell therapy too restrictive. Extension of wound area to 1-10 cm² and the inclusion of neuro-ischaemic ulcers increased eligibility for enrolment from 1.4 to 20 %.