diff --git a/dangerzone/conversion/pixels_to_pdf.py b/dangerzone/conversion/pixels_to_pdf.py
index cbc0c86..144b2de 100644
--- a/dangerzone/conversion/pixels_to_pdf.py
+++ b/dangerzone/conversion/pixels_to_pdf.py
@@ -11,12 +11,13 @@ import json
 import os
 import shutil
 import sys
+from typing import Optional
 
 from .common import DangerzoneConverter, running_on_qubes
 
 
 class PixelsToPDF(DangerzoneConverter):
-    async def convert(self) -> None:
+    async def convert(self, ocr_lang: Optional[str] = None) -> None:
         self.percentage = 50.0
 
         num_pages = len(glob.glob("/tmp/dangerzone/page-*.rgb"))
@@ -43,7 +44,7 @@ class PixelsToPDF(DangerzoneConverter):
             total_size += page_size
             timeout = self.calculate_timeout(page_size, 1)
 
-            if os.environ.get("OCR") == "1":  # OCR the document
+            if ocr_lang:  # OCR the document
                 self.update_progress(
                     f"Converting page {page}/{num_pages} from pixels to searchable PDF"
                 )
@@ -71,7 +72,7 @@ class PixelsToPDF(DangerzoneConverter):
                         png_filename,
                         ocr_filename,
                         "-l",
-                        os.environ.get("OCR_LANGUAGE"),  # type: ignore
+                        ocr_lang,
                         "--dpi",
                         "70",
                         "pdf",
@@ -152,10 +153,11 @@ class PixelsToPDF(DangerzoneConverter):
 
 
 async def main() -> int:
+    ocr_lang = os.environ.get("OCR_LANGUAGE") if os.environ.get("OCR") == "1" else None
     converter = PixelsToPDF()
 
     try:
-        await converter.convert()
+        await converter.convert(ocr_lang)
         error_code = 0  # Success!
 
     except (RuntimeError, TimeoutError, ValueError) as e:
diff --git a/dangerzone/isolation_provider/qubes.py b/dangerzone/isolation_provider/qubes.py
index e620123..c5e4b85 100644
--- a/dangerzone/isolation_provider/qubes.py
+++ b/dangerzone/isolation_provider/qubes.py
@@ -176,25 +176,17 @@ class Qubes(IsolationProvider):
                 f"Conversion output (doc to pixels)\n{self.sanitize_conversion_str(untrusted_log)}"
             )
 
-        # FIXME pass OCR stuff properly (see #455)
-        old_environ = dict(os.environ)
-        if ocr_lang:
-            os.environ["OCR"] = "1"
-            os.environ["OCR_LANGUAGE"] = ocr_lang
-
         def print_progress_wrapper(error: bool, text: str, percentage: float) -> None:
             self.print_progress_trusted(document, error, text, percentage)
 
-        asyncio.run(PixelsToPDF(progress_callback=print_progress_wrapper).convert())
+        asyncio.run(
+            PixelsToPDF(progress_callback=print_progress_wrapper).convert(ocr_lang)
+        )
 
         percentage = 100.0
         text = "Safe PDF created"
         self.print_progress_trusted(document, False, text, percentage)
 
-        # FIXME remove once the OCR args are no longer passed with env vars
-        os.environ.clear()
-        os.environ.update(old_environ)
-
         shutil.move(CONVERTED_FILE_PATH, document.output_filename)
         success = True