Interlaboratory Comparison Reveals State of the Art in Microplastic Detection and Quantification Methods

\ua9 2025 The Authors. Published by American Chemical Society. In this study, we investigate the current accuracy of widely used microplastic (MP) detection methods through an interlaboratory comparison (ILC) involving ISO-approved techniques. The ILC was organized under the prestandardization platform of VAMAS (Versailles Project on Advanced Materials and Standards) and gathered a large number (84) of analytical laboratories across the globe. The aim of this ILC was (i) to test and to compare two thermo-analytical and three spectroscopical methods with respect to their suitability to identify and quantify microplastics in a water-soluble matrix and (ii) to test the suitability of the microplastic test materials to be used in ILCs. Two reference materials (RMs), polyethylene terephthalate (PET) and polyethylene (PE) as powders with rough size ranges between 10 and 200 μm, were used to press tablets for the ILC. The following parameters had to be assessed: polymer identity, mass fraction, particle number concentration, and particle size distribution. The reproducibility, SR, in thermo-analytical experiments ranged from 62%-117% (for PE) and 45.9%-62% (for PET). In spectroscopical experiments, the SR varied between 121% and 129% (for PE) and 64% and 70% (for PET). Tablet dissolution turned out to be a very challenging step and should be optimized. Based on the knowledge gained, development of guidance for improved tablet filtration is in progress. Further, in this study, we discuss the main sources of uncertainties that need to be considered and minimized for preparation of standardized protocols for future measurements with higher accuracy

Interlaboratory comparison reveals state of the art in microplastic detection and quantification methods

In this study, we investigate the current accuracy of widely used microplastic (MP) detection methods through an interlaboratory comparison (ILC) involving ISO-approved techniques. The ILC was organized under the prestandardization platform of VAMAS (Versailles Project on Advanced Materials and Standards) and gathered a large number (84) of analytical laboratories across the globe. The aim of this ILC was (i) to test and to compare two thermo-analytical and three spectroscopical methods with respect to their suitability to identify and quantify microplastics in a water-soluble matrix and (ii) to test the suitability of the microplastic test materials to be used in ILCs. Two reference materials (RMs), polyethylene terephthalate (PET) and polyethylene (PE) as powders with rough size ranges between 10 and 200 μm, were used to press tablets for the ILC. The following parameters had to be assessed: polymer identity, mass fraction, particle number concentration, and particle size distribution. The reproducibility, SR, in thermo-analytical experiments ranged from 62%–117% (for PE) and 45.9%–62% (for PET). In spectroscopical experiments, the SR varied between 121% and 129% (for PE) and 64% and 70% (for PET). Tablet dissolution turned out to be a very challenging step and should be optimized. Based on the knowledge gained, development of guidance for improved tablet filtration is in progress. Further, in this study, we discuss the main sources of uncertainties that need to be considered and minimized for preparation of standardized protocols for future measurements with higher accuracy

briandfoy/PerlPowerTools: PerlPowerTools-1.039

1.039 2023-09-22T23:46:44Z * All of these improvements are from Michael Mikonos * arithmetic - terminate on end-of-line * banner - clarify usage (#232) * basename - fix directory separator handling (#250) * bc - fix integer precision problem (#236) * bcd - add -d to decode card (#238) * cal - improve year formatting (#242) * cmp - check that both files exist (#249) * diff - work with directory arguments (#240) (#241) * ed - fix current line tracking for j, m, t (#225) - add wq shortcut (#228) - fix handling of bad command 1c0 (#251) * expr - exit with error for missing argument (#253) * fold - continue if there's an error (#226) * head - don't head on directories (#227) * ls - use standard meaning of -f (turns on -a) (#245) * nl - validate numeric operations (#229) - exit with error for bad filename (#230) * paste - specify stdin with - (#231) - reject unknown options (#235) * rmdir - include filename in warnings (#243) * seq - added new command (#257) * sort - don't continue for unknown options (#255) * sum - improve code readability (#239) * tee - handle -n properly (#254) * tsort - don't support multiple input files (#256) * which - fix option parsing (#246) * xargs - fix infinite loop with -n (#248

briandfoy/PerlPowerTools: PerlPowerTools-1.043

<p>1.043 2024-01-25T23:23:48Z * All changes are from Michael Mikonos unless otherwise noted * ar - get rid of getopts.pl (#394) - switch to three argument opens (#398) * cat - fail for -? (#396) * cmp - simplify some code (#388) * col - no longer takes arguments; it's just stdin (#407) * ed - fix some line calculation (#405, #413, #414, #415) - allow whitespace in arguments (#411) - fail for -? (#417) * file - switch to three argument opens (#398) * fish - update some style in the code (#410) * fortune - unknown options are now fatal (#392) * grep - remove some stray chars from error messages (#400) * hangman - don't assume size of word list (#416) * head - the - is now treated as stdin (#397) * ls - add strict (#395) * od - fix line offset numbers in output (#389) - fix oddities in output with -b (#391) * pom - unknown options are now fatal (#390) * pr - -3x option are now fatal (#393) * primes - non-numeric data are errors now (#406) * sort - enough sensible bounds for -F and -y (#412) * tail - allow both -n1 (combined) and -n 1 (separated) (#399)</p&gt

briandfoy/PerlPowerTools: PerlPowerTools-1.044

<p>1.044 2024-03-03T09:12:25Z * All changes are from Michael Mikonos * addbib - allow file named 0 for -p (#472)</p> <pre><code>* apply - fix argument handling for %N handling (#436) - simplify some internals (#471) * arch - reject all arguments (#438) * asa - fix problem reading a file with a dash in name (#476) * basename - exit with an error for no arguments (#448) * bc - the - is a literal filename now (#444) - a couple of internal cleanups (#451) - don't print value after array element assignment (#452) * cat - explicitly close files (#423) - terminate line number with a tab (#442) * cmp - fix off-by-one error (#450) - require at least two arguments (#465) * colrm - some internal improvements (#462) * cp - report correct exit code (#426) * deroff - allow reading from standard input (#474) * diff - reduce internal clutter (#458) * dirname - exit with an error for no arguments (#448) * ed - internal improvements (#418) - simply the debug facility (#432) - clean up some internals (#437) - fix applying a substitution to a single line (#441) - improvements to `r filename` and `w filename` (#459) - refactor some of the insertion code (#466) * env - print usage for bad options (#461) * expand - fix command line processing regex (#469) * fish - reduce some internal complexity (#449) * fmt - handle -<DIGIT> as option instead of a file (#431) * fold - terminate command-line options with -- (#425) - don't treat - as standard input (#447) * grep - remove TCGREP environment var, use GREP_OPTIONS instead (#428) * head - handle - option to be like -n <DIGIT> (#419) * id - remove -h option, although you still get the usage statement (#429) - note that -a is ignored (#445) * install - some internal improvements on usage handling (#424) * kill - validate signal number arguments (#454) * look - standardize exit codes (#473) * maze - fix the usage message (#443) * nl - validate the -n argument (#446) - specify exactly one file on the command line (#479) * od - some internal improvements (#433) - fix offset numbering (#434) - support multiple input files (#463) * paste - require at least one filename; - is standard input (#440) - internal improvements for handling field separator (#460) * ping - reject unknown arguments (#477) * primes - fail for too many arguments (#470) * rev - terminate args with -- (#439) * rm - document the -v switch (#421) * shar - handle missing or unreadable files (#475) * sleep - fail for extra arguments (#430) * tac - fix some odd cases for -s (#467) * tail - handle -<DIGIT> option to be like `-n <DIGIT>` (#420) * tee - end command line options with -- (#480) * touch - fix usage handling and exit code (#468) * uname - reject any arguments (#478) * uniq - reject unknown command-line options (#422) * wc - terminate argument processing with -- (#427) - fix -w to report the right number (#457) * what - invalid options die; no longer supports stdin (#456) * whoami - don't allow arguments (#453) * xargs - -l is an alias for -L (GNU extension) (#435) * yes - remove GNU extensions (we are a BSD clone) (#455)</code></pre&gt

briandfoy/PerlPowerTools: PerlPowerTools-1.045

<p>1.045 2024-04-30T22:22:10Z * All changes from Michael Mikonos * ar - validate args for -a and -b (#484) - ensure file has header with -q, which should have happened before but wasn't (#495) - warn if archive member isn't found (#500) - improve internals with strict; better option validation (#510)</p> <pre><code>* arithmetic - validate the -r argument using the right variable (#501) - treat an empty line as bad input instead of the number undef (#541) * asa - various internals improvements (#545) * awk - don't need to load App::a2p (#524) - various internals improvements (#525) - use File::Temp instead of rolling our own (#557) * banner - various internals improvements (#585) * bc - handle cases where Math::Big* is missing (like minimal distros of perl) (#511) - assignment to variable does not print, in line with GNU bc (#517) - remove non-standard ** operator; use ^ instead (#518) - catch negative index in array assignment (#521) - allow digits in array names (#523) - internal fixes to make the yydebug code simpler (#540) - various internals improvements (#543) - various internals improvements (#548) - various internals improvements (#554) - various internals improvements (#559) - fix "Exiting subroutine via next" error (#562) - catch divide by zero before we try the division (#580) - fix problem where vars did not have a type in the internal symbol table (fixes #522) (#582) - allow array indices to have fractional parts (still only use the floor) (#584) * cal - simplify usage message (#583) * cmp - remove -? option, although using it give you the help still (#567) * col - we now buffer the entire file to get around some weird effects (#483) - various internals improvements (#586) * comm - allow for the unbundling of options (#535) * cut - don't allow -b and -f at the same time (#485) - various internals improvements (#588) * date - protect path to current perl in backticks (from kal24) (#506) - various internals improvements (#509) * diff - empty files are the same (#578) * du - warn if du cannot stat a file (#515) - various internals improvements (#574) * echo - various internals improvements (#509) * ed - internal improvements to reduce complexity (#489) - filename must have at least one character; better support to remember filename (#542) - various internals improvements (#550) - various internals improvements (#553) - fixed inserting an empty file; print the number of characters read from a file (#560) - handle argument to `s` command being zero length (#577) - s/// correctly reports "no match" for no matches. (#579) * expand - fix the tabstop argument to get the correct number of spaces (#491) - allow for the -- option terminator (#492) * factor - various internals improvements (#509) * file - exit with error if the command line options are wrong (#546) - various internals improvements (#571) * fish - various internals improvements (#544) - card names are now case insensitive (#551) - various internals improvements (#558) * fmt - better reporting when the program cannot open a file (#487) * fold - better error messages when fold can't close a file properly (#561) * glob - handle a bare tilde at the start of the path (#490) - various internals improvements (#509) - various internals improvements (#539) * hangman - ensure that we can get at least one word from the word list (#502) * id - allow only 0 or 1 arguments (#494) * install - fix setting permissions on installed files (#514) * join - allow -- to terminate options (#504) * kill - help shows signal list (#513) - pid must be a positive whole number (#534) - various internals improvements (#566) * ln - handle single argument call correctly (#497) * mail - resolve conflicting hostname() definitions (#519) - use error from IO::Socket if there's a problem (#536) * maze - clarify argument processing (#516) * mkdir - various internals improvements (#549) - die for an empty mode argument (#552) * mkfifo - various internals improvements (#572) * moo - argument must be greater than zero (#569) * nl - validate arguments to -b, -f, and -h (#496) * od - correctly handle multiline repeating (#498) * patch - only process regular files, and die otherwise (#556) * pig - remove -v but support --version (#587) * printenv - remove -? option to match BSD (#503) * printf - remove internal string eval to allow more things in formats and args (#526) - handle octal and hex escapes better (and limit to a single char) (#528) - ignore arguments if the first argument does not have format specifiers (#532) - better error message for bad printf format (#564) * pwd - various internals improvements (#573) * rev - remove -v option, but add it back as --version; -h and --version messages change slightly (#581) * rmdir - don't rmdir() if the argument is not a directory (#568) * shar - various internals improvements (#565) * spell - remove -b option, use -d instead to use alternate dictionary (#527) - fail if dictionary is empty (#530) * split - disallow a split size of 0 (#482) - various internals improvements (#555) * sum - don't allow -a and -o at the same time (#488) * tac - validate the value for -S; must be positive (#529) * tail - exit with error if the command line options are wrong (#547) * tar - fix file extraction (#493) - -f switch is now mandatory; use - to read from stdin (#575) * test - exit 1 (not 2) for no arguments. (#520) * touch - de-emphasize -f, which is a no-op anyway (#512) - -r can now take a filename named "0" (#563) - various internals improvements (#576) * unexpand - -- terminates options processing (#499) * units - various internals improvements (#509) - remove --copying and --warranty options (license is in this distro) (#589) * unshar - terminate arguments with -- (#481) * which - use the same exit codes as the GNU version (#486) * whois - fix some network code; don't use a default server (must specify a server) (#531) - query multiple domains in one command (#533) - make strict safe; use error from IO::Socket instead of $! (#537) - hostname must have at least one non-whitespace character (#538)</code></pre&gt

Interlaboratory Comparison Reveals State of the Art in Microplastic Detection and Quantification Methods

In this study, we investigate the current accuracy of widely used microplastic (MP) detection methods through an interlaboratory comparison (ILC) involving ISO-approved techniques. The ILC was organized under the prestandardization platform of VAMAS (Versailles Project on Advanced Materials and Standards) and gathered a large number (84) of analytical laboratories across the globe. The aim of this ILC was (i) to test and to compare two thermo-analytical and three spectroscopical methods with respect to their suitability to identify and quantify microplastics in a water-soluble matrix and (ii) to test the suitability of the microplastic test materials to be used in ILCs. Two reference materials (RMs), polyethylene terephthalate (PET) and polyethylene (PE) as powders with rough size ranges between 10 and 200 μm, were used to press tablets for the ILC. The following parameters had to be assessed: polymer identity, mass fraction, particle number concentration, and particle size distribution. The reproducibility, SR, in thermo-analytical experiments ranged from 62%-117% (for PE) and 45.9%-62% (for PET). In spectroscopical experiments, the SR varied between 121% and 129% (for PE) and 64% and 70% (for PET). Tablet dissolution turned out to be a very challenging step and should be optimized. Based on the knowledge gained, development of guidance for improved tablet filtration is in progress. Further, in this study, we discuss the main sources of uncertainties that need to be considered and minimized for preparation of standardized protocols for future measurements with higher accuracy

Current Trends in Development of Photosynthetic Bioelectrochemical Systems for Light Energy Conversion

During the past few decades, intensive research has been focused on the application of biological photosynthetic processes for "green" electrical power generation. In this contribution, we consider different possible photobiocatalysts, such as isolated photosystems, thylakoid membranes (TMs), and whole photosynthetic organisms suitable for building bioelectrochemical systems for light energy conversion. We discuss numerous approaches to immobilization and wiring of the photobioagents on conductive surfaces and various electrode materials and mediators employed in state-of-the-art photobioelectrochemical systems, and we highlight the latest achievements in photocurrent intensity and power output of the solar-driven biodevices